Patrick Joseph Kelly, M.D.

Multiple synchronous gliomas of distinctly different grades
Kelly, Patrick J
2010 ;1:49-49, Surgical neurology international
— id: 114060, year: 2010, vol: 1, page: 49, stat: Journal Article,

Insular gliomas and lenticulostriate artery position RESPONSE
Kelly, PJ; Moshel, Y
2009 DEC ;111(6):1294-1295, Journal of neurosurgery
— id: 105713, year: 2009, vol: 111, page: 1294, stat: Journal Article,

Occipital transtentorial approach to the precentral cerebellar fissure and posterior incisural space
Moshel, Yaron A; Parker, Erik C; Kelly, Patrick J
2009 Sep;65(3):554-564, Neurosurgery
OBJECTIVE: To describe the surgical techniques and postoperative clinical outcomes with the occipital transtentorial (OT) approach in patients harboring lesions arising from the precentral cerebellar fissure, posterior incisural space, and adjoining structures. METHODS: Twenty-two patients underwent microsurgical resection of intra-axial lesions arising within the precentral cerebellar fissure and posterior incisural space between 1997 and 2006. Patient demographics, presenting symptoms, pathology, and neurological outcomes were retrospectively reviewed. Pre- and postoperative magnetic resonance imaging scans were evaluated to determine the anatomic extensions of the lesion and the degree of surgical resection. Patients with lesions primarily confined to the pineal and posterior third ventricle approached by a supracerebellar infratentorial trajectory were excluded from this study. RESULTS: Of the 22 patients reported in this series, 17 (77%) had contrast-enhancing lesions, and 5 (23%) had nonenhancing lesions arising from the precentral cerebellar fissure and posterior incisural space. The lesions were oriented dorsomedial to the midbrain and diencephalon in 6 patients (27%), dorsolateral in 14 patients (64%), and lateral in 2 patients (9%). A lateral OT approach directed under the occipitotemporal junction was used in 16 patients (73%), and an interhemispheric OT approach was used in 6 patients (27%). Transient visual field loss occurred in 3 patients (14%); it resolved by the third follow-up month. Gross total resection or near-total resection of the imaging-defined lesion volume was achieved in 19 patients (86%). CONCLUSION: The OT approaches provide excellent exposure for lesions of the precentral cerebellar fissure, posterior incisural space, and adjacent structures. The lateral OT approach directed under the occipitotemporal junction provides an inline view for lesions situated posterolateral to the brainstem. It also provides an inferiorly directed view under the venous system into the precentral cerebellar fissure and fourth ventricular roof. Visual field deficits are minimized by directing the trajectory under the occipitotemporal junction instead of retracting along the interhemispheric corridor. The interhemispheric OT approach was primarily used for lesions extending superiorly, in the midline or near midline, above the tentorium and venous system into the splenium of corpus callosum, lateral ventricle, and posterior thalamus, where extensive lateral retraction was not required
— id: 101648, year: 2009, vol: 65, page: 554, stat: Journal Article,

Antiangiogenic therapy using bevacizumab in recurrent high-grade glioma: impact on local control and patient survival
Narayana, Ashwatha; Kelly, Patrick; Golfinos, John; Parker, Erik; Johnson, Glyn; Knopp, Edmond; Zagzag, David; Fischer, Ingeborg; Raza, Shahzad; Medabalmi, Praveen; Eagan, Patricia; Gruber, Michael L
2009 Jan;110(1):173-180, Journal of neurosurgery
Object Antiangiogenic agents have recently shown impressive radiological responses in high-grade glioma. However, it is not clear if the responses are related to vascular changes or due to antitumoral effects. The authors report the mature results of a clinical study of bevacizumab-based treatment of recurrent high-grade gliomas. Methods Sixty-one patients with recurrent high-grade gliomas received treatment with bevacizumab at 10 mg/kg every 2 weeks for 4 doses in an 8-week cycle along with either irinotecan or carboplatin. The choice of concomitant chemotherapeutic agent was based on the number of recurrences and prior chemotherapy. Results At a median follow-up of 7.5 months (range 1-19 months), 50 (82%) of 61 patients relapsed and 42 patients (70%) died of the disease. The median number of administered bevacizumab cycles was 2 (range 1-7 cycles). The median progression-free survival (PFS) and overall survival (OS) were 5 (95% confidence interval [CI] 2.3-7.7) and 9 (95% CI 7.6-10.4) months, respectively, as calculated from the initiation of the bevacizumab-based therapy. Radiologically demonstrated responses following therapy were noted in 73.6% of cases. Neither the choice of chemotherapeutic agent nor the performance of a resection prior to therapy had an impact on patient survival. Although the predominant pattern of relapse was local, 15 patients (30%) had diffuse disease. Conclusions Antiangiogenic therapy using bevacizumab appears to improve survival in patients with recurrent high-grade glioma. A possible change in the invasiveness of the tumor following therapy is worrisome and must be closely monitored
— id: 90721, year: 2009, vol: 110, page: 173, stat: Journal Article,

Glioma vascularity correlates with reduced patient survival and increased malignancy
Russell, Stephen M; Elliott, Robert; Forshaw, David; Golfinos, John G; Nelson, Peter K; Kelly, Patrick J
2009 Sep;72(3):242-246, Surgical neurology
BACKGROUND: The objective of this study was 2-fold: (1) document the presence and degree of vascularity in gliomas of different pathologic grades and (2) determine whether the presence of abnormal vascularity, determined by catheter angiography, correlates with a shortened survival. METHODS: As part of a protocol for radiographic data acquisition that was used in a computer-assisted, stereotactic system, all patients who underwent biopsy or resection of a newly diagnosed glioma between 1994 and 2000 at our institution routinely underwent preoperative catheter angiography. The presence and degree of tumor vascularity were recorded and then correlated with survival and pathologic grade. The confounding effects of age, KPS, adjuvant treatment, and extent of resection on survival were considered. RESULTS: Two hundred thirty-one patients were included in this study. The mean follow-up of survivors was 7.8 years. Tumor vascularity correlated with a shortened survival (proportional hazards RR for survival, 0.69; 95% CI, 0.58-0.82). This correlation persisted after correction for age, KPS score, adjuvant therapy, and extent of resection (RR, 0.81; 95% CI, 0.68-0.97). Abnormal vascularity was present in 25 (30%) of 82 low-grade (WHO grade 2) gliomas. Overall, the extent of vascularity (none [120 patients, 52%], blush [63 patients, 27%], neovessels [25 patients, 11%], and arteriovenous shunting [23 patients, 10%]) correlated with worse WHO tumor grade (P < .0001). CONCLUSIONS: The presence of abnormal vascularity correlates with both a shortened survival and higher grade of malignancy. These findings underscore the importance of antiangiogenesis factor investigation and drug development for the treatment of gliomas, regardless of their pathologic grade
— id: 101316, year: 2009, vol: 72, page: 242, stat: Journal Article,

High-grade glioma before and after treatment with radiation and Avastin: initial observations
Fischer, Ingeborg; Cunliffe, Clare H; Bollo, Robert J; Raza, Shahzad; Monoky, David; Chiriboga, Luis; Parker, Erik C; Golfinos, John G; Kelly, Patrick J; Knopp, Edmond A; Gruber, Michael L; Zagzag, David; Narayana, Ashwatha
2008 Oct;10(5):700-708, Neuro-oncology
We evaluate the effects of adjuvant treatment with the angiogenesis inhibitor Avastin (bevacizumab) on pathological tissue specimens of high-grade glioma. Tissue from five patients before and after treatment with Avastin was subjected to histological evaluation and compared to four control cases of glioma before and after similar treatment protocols not including bevacizumab. Clinical and radiographic data were reviewed. Histological analysis focused on microvessel density and vascular morphology, and expression patterns of vascular endothelial growth factor-A (VEGF-A) and the hematopoietic stem cell, mesenchymal, and cell motility markers CD34, smooth muscle actin, D2-40, and fascin. All patients with a decrease in microvessel density had a radiographic response, whereas no response was seen in the patients with increased microvessel density. Vascular morphology showed apparent 'normalization' after Avastin treatment in two cases, with thin-walled and evenly distributed vessels. VEGF-A expression in tumor cells was increased in two cases and decreased in three and did not correlate with treatment response. There was a trend toward a relative increase of CD34, smooth muscle actin, D2-40, and fascin immunostaining following treatment with Avastin. Specimens from four patients with recurrent malignant gliomas before and after adjuvant treatment (not including bevacizumab) had features dissimilar from our study cases. We conclude that a change in vascular morphology can be observed following antiangiogenic treatment. There seems to be no correlation between VEGF-A expression and clinical parameters. While the phenomena we describe may not be specific to Avastin, they demonstrate the potential of tissue-based analysis for the discovery of clinically relevant treatment response biomarkers
— id: 91374, year: 2008, vol: 10, page: 700, stat: Journal Article,

A neurosurgeon speaks out
Kelly, Patrick J
2008 Feb;69(2):214-215, Surgical neurology
— id: 135324, year: 2008, vol: 69, page: 214, stat: Journal Article,

Resection of insular gliomas: the importance of lenticulostriate artery position
Moshel, Yaron A; Marcus, Joshua D S; Parker, Erik C; Kelly, Patrick J
2008 Nov;109(5):825-834, Journal of neurosurgery
OBJECT: The object of this study was to identify characteristic preoperative angiographic and MR imaging features of safely resectable insular gliomas and describe the surgical techniques and postoperative clinical outcomes. METHODS: Thirty-eight patients with insular gliomas underwent transsylvian resection between 1995 and 2007. Patient demographics, presenting symptoms, pathological findings, and neurological outcomes were retrospectively reviewed. Preoperative MR imaging-defined tumor volumes were superimposed onto the preoperative stereotactic cerebral angiograms to determine whether the insular tumor was confined lateral to (Group I) or extended medially around (Group II) the lenticulostriate arteries (LSAs). RESULTS: Twenty-five patients (66%) had tumors situated lateral to the LSAs and 13 (34%) had tumors encasing the LSAs. Insular gliomas situated lateral to the LSAs led to significant medial displacement of these vessels (161 +/- 39%). In 20 (80%) of these 25 cases the boundaries between tumor and brain parenchyma were well demarcated on preoperative T2-weighted MR images. In contrast, there was less displacement of the LSAs (130 +/- 14%) in patients with insular gliomas extending around the LSAs on angiography. In 11 (85%) of these 13 cases, the tumor boundaries were diffuse on T2-weighted MR images. Postoperative hemiparesis or worsening of a preexisting hemiparesis, secondary to LSA compromise, occurred in 5 patients, all of whom had tumor volumes that extended medial to the LSAs. Gross-total or near-total resection was achieved more frequently in cases in which the insular glioma remained lateral to the LSAs (84 vs 54%). CONCLUSIONS: Insular gliomas with an MR imaging-defined tumor volume located lateral to the LSAs on stereotactic angiography displace the LSAs medially by expanding the insula, have well-demarcated tumor boundaries on MR images, and can be completely resected with minimal neurological morbidity. In contrast, insular tumors that appear to surround the LSAs do not displace these vessels medially, are poorly demarcated from normal brain parenchyma on MR images, and are associated with higher rates of neurological morbidity if aggressive resection is pursued. Preoperative identification of these anatomical growth patterns can be of value in planning resection
— id: 93383, year: 2008, vol: 109, page: 825, stat: Journal Article,

Change in pattern of relapse following anti-angiogenic therapy in high grade glioma
Narayana, A; Golfinos, JG; Raza, S; Knopp, E; Medabalmi, P; Parker, E; Kelly, P; Zagzag, D; Gruber, M
2008 AUG ;72(1):S11-S11, International journal of radiation oncology biology physics
— id: 86794, year: 2008, vol: 72, page: S11, stat: Journal Article,

Feasibility of using bevacizumab with radiation therapy and temozolomide in newly diagnosed high-grade glioma
Narayana, Ashwatha; Golfinos, John G; Fischer, Ingeborg; Raza, Shahzad; Kelly, Patrick; Parker, Erik; Knopp, Edmond A; Medabalmi, Praveen; Zagzag, David; Eagan, Patricia; Gruber, Michael L
2008 Oct 1;72(2):383-389, International journal of radiation oncology biology physics
INTRODUCTION: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor (VEGF), has shown promise in the treatment of patients with recurrent high-grade glioma. The purpose of this study is to test the feasibility of using bevacizumab with chemoradiation in the primary management of high-grade glioma. METHODS AND MATERIALS: Fifteen patients with high-grade glioma were treated with involved field radiation therapy to a dose of 59.4 Gy at 1.8 Gy/fraction with bevacizumab 10 mg/kg on Days 14 and 28 and temozolomide 75 mg/m(2). Subsequently, bevacizumab 10 mg/kg was continued every 2 weeks with temozolomide 150 mg/m(2) for 12 months. Changes in relative cerebral blood volume, perfusion-permeability index, and tumor volume measurement were measured to assess the therapeutic response. Immunohistochemistry for phosphorylated VEGF receptor 2 (pVEGFR2) was performed. RESULTS: Thirteen patients (86.6%) completed the planned bevacizumab and chemoradiation therapy. Four Grade III/IV nonhematologic toxicities were seen. Radiographic responses were noted in 13 of 14 assessable patients (92.8%). The pVEGFR2 staining was seen in 7 of 8 patients (87.5%) at the time of initial diagnosis. Six patients have experienced relapse, 3 at the primary site and 3 as diffuse disease. One patient showed loss of pVEGFR2 expression at relapse. One-year progression-free survival and overall survival rates were 59.3% and 86.7%, respectively. CONCLUSION: Use of antiangiogenic therapy with radiation and temozolomide in the primary management of high-grade glioma is feasible. Perfusion imaging with relative cerebral blood volume, perfusion-permeability index, and pVEGFR2 expression may be used as a potential predictor of therapeutic response. Toxicities and patterns of relapse need to be monitored closely
— id: 91373, year: 2008, vol: 72, page: 383, stat: Journal Article,

Guidelines of the Pituitary Society for the diagnosis and management of prolactinomas. [Spanish]
Casanueva F.F.; Molitch M.E.; Schlechte J.A.; Abs R.; Bonert V.; Bronstein M.D.; Brue T.; Cappabianca P.; Colao A.; Fahlbusch R.; Fideleff H.; Hadani M.; Kelly P.; Kleinberg D.; Laws E.; Marek J.; Scanlon M.; Sobrinho L.G.; Wass J.A.H.; Giustina A.
2007 ;54(8):438.e1-438.e10, Endocrinologia y Nutricion
— id: 74878, year: 2007, vol: 54, page: 438.e1, stat: Journal Article,

Stereotactic volumetric resection of thalamic pilocytic astrocytomas
Moshel, Yaron A; Link, Michael J; Kelly, Patrick J
2007 Jul;61(1):66-75, Neurosurgery
OBJECTIVE: To describe the surgical approaches, the radiographic and clinical outcomes, and the long-term follow-up of patients harboring thalamic pilocytic astrocytomas after radical resection by means of a stereotactic volumetric technique. METHODS: Seventy-two patients with thalamic pilocytic astrocytomas underwent stereotactic volumetric resection by the senior author (PJK) at the Mayo Clinic between 1984 and 1993 (44 patients) and at New York University Medical Center between 1993 and 2005 (28 patients). Patient demographics, presenting symptoms, surgical approaches, neurological outcomes, pathology, initial postoperative status, and long-term clinical and radiographic follow-up were retrospectively reviewed. RESULTS: On preoperative neurological examinations, 54 of the 72 patients had neurological deficits; of these, 48 had hemiparesis. Postoperative imaging demonstrated gross total resection in 58 patients and minimal (<6 mm) residual tumor in 13 patients. Tumor resection was aborted in one patient. On immediate postoperative examination, 16 patients had significant improvements in hemiparesis. Six patients had worsening of a preexisting hemiparesis and one had a new transient postoperative hemiparesis. There was one postoperative death. After 13 to 20 years of follow-up in the Mayo group (mean, 15 +/- 3 yr) and 1 to 13 years of follow-up in the New York University group (mean, 8 +/- 3 yr), 67 patients were recurrence/progression-free, one had tumor recurrence, and three had progression of residual tumor. There were two shunt-related deaths. On long-term neurological follow-up, 27 patients had significant improvements in hemiparesis; one patient with a postoperative worsening of a preexisting hemiparesis remained unchanged. There were no patients with new long-term motor deficits after stereotactic resection. CONCLUSION: Gross total removal of thalamic pilocytic astrocytomas with low morbidity and mortality can be achieved by computer-assisted stereotactic volumetric resection techniques. Gross total resection of these lesions confers a favorable long-term prognosis without adjuvant chemotherapy and/or radiation therapy and leads to the improvement of neurological deficits
— id: 73385, year: 2007, vol: 61, page: 66, stat: Journal Article,

Long-term changes in motor function and stimulation parameters in patients with deep brain stimulation of the subthalamic nucleus for Parkinson's disease
Parker, EC; Beric, A; Sterio, D; Drafta, C; Xu, M; Taverna, PA; Kelly, PJ
2007 JAN-FEB ;85(1):30-31, Stereotactic & functional neurosurgery
— id: 70324, year: 2007, vol: 85, page: 30, stat: Journal Article,

Incidence and clinical evolution of postoperative deficits after volumetric stereotactic resection of glial neoplasms involving the supplementary motor area
Russell, Stephen M; Kelly, Patrick J
2007 Jul;61(1 Suppl):358-367, Neurosurgery
OBJECTIVE: We report the incidence and clinical evolution of postoperative deficits and supplementary motor area (SMA) syndrome after volumetric stereotactic resection of glial neoplasms involving the posterior one-third of the superior frontal convolution. We investigated variables that may be associated with the occurrence of SMA syndrome. METHODS: The postoperative clinical status of 27 consecutive patients who underwent resection of SMA gliomas was retrospectively reviewed. Neurological examination results were recorded 1 day, 1 week, 1 month, and 6 months postoperatively. The extent of tumor resection, the percentage of SMA resection, violation of the cingulate gyrus, and operative complications were tabulated. RESULTS: The overall incidence of SMA-related deficits was 26% (7 of 27 patients), with 3 patients having complete SMA syndrome and 4 patients having partial SMA syndrome. Two additional patients (7.5%) had other postoperative deficits, including one with mild facial weakness and one with transient aphasia. The resection of low-grade gliomas was associated with a higher incidence of SMA syndrome, an outcome that likely reflects more complete removal of functional SMA cortex in this subset of patients. Intraoperative monitoring localized the precentral sulcus within the preoperatively defined tumor volume in 6 (22%) of 27 patients, thereby precluding gross total resection. All 27 patients had excellent outcomes at the 6-month follow-up examination. CONCLUSION: When the resection of SMA gliomas is limited to the radiographic tumor boundaries, the incidence and severity of SMA syndrome may be minimized. With the use of these resection parameters, patients with high-grade SMA gliomas are unlikely to experience SMA syndrome. These findings are helpful in the preoperative counseling of patients who are to undergo cytoreductive resection of SMA gliomas
— id: 94595, year: 2007, vol: 61, page: 358, stat: Journal Article,

Guidelines of the Pituitary Society for the diagnosis and management of prolactinomas
Casanueva, FF; Molitch, ME; Schlechte, JA; Abs, R; Bonert, V; Bronstein, MD; Brue, T; Cappabianca, P; Colao, A; Fahlbusch, R; Fideleff, H; Hadani, M; Kelly, P; Kleinberg, D; Laws, E; Marek, J; Scanlon, M; Sobrinho, LG; Wass, JAH; Giustina, A
2006 AUG ;65(2):265-273, Clinical endocrinology
In June 2005, an ad hoc Expert Committee formed by the Pituitary Society convened during the 9th International Pituitary Congress in San Diego, California. Members of this committee consisted of invited international experts in the field, and included endocrinologists and neurosurgeons with recognized expertise in the management of prolactinomas. Discussions were held that included all interested participants to the Congress and resulted in formulation of these guidelines, which represent the current recommendations on the diagnosis and management of prolactinomas based upon comprehensive analysis and synthesis of all available data
— id: 98071, year: 2006, vol: 65, page: 265, stat: Journal Article,

History of the cushing reflex
Fodstad, Harald; Kelly, Patrick J; Buchfelder, Michael
2006 Nov;59(5):1132-1137, Neurosurgery
Increasing systolic and pulse pressure with bradycardia and respiratory irregularity are signs of increased intracranial pressure, leading to cerebral herniation and fatal brainstem compression. This phenomenon, the vasopressor response, is generally known as the Cushing reflex based on Harvey Cushing's experimental work in Europe in 1901 and 1902. However, similar experiments had been carried out decades earlier by others, notably Paul Cramer, Ernst von Bergmann, Ernst von Leyden, Georg Althann, Friedrich Jolly, Friedrich Pagenstecher, Henri Duret, Bernard Naunyn, and Julius Schreiber. Cushing initially failed to give credit to the work of these predecessors. Nonetheless, he studied the brain's reaction to compression more carefully than previous researchers and offered an improved explanation of the pathophysiology of the phenomenon named after him
— id: 69608, year: 2006, vol: 59, page: 1132, stat: Journal Article,

Randomized controlled trial of intraputamenal glial cell line-derived neurotrophic factor infusion in Parkinson disease
Lang, Anthony E; Gill, Steven; Patel, Nik K; Lozano, Andres; Nutt, John G; Penn, Richard; Brooks, David J; Hotton, Gary; Moro, Elena; Heywood, Peter; Brodsky, Matthew A; Burchiel, Kim; Kelly, Patrick; Dalvi, Arif; Scott, Burton; Stacy, Mark; Turner, Dennis; Wooten, V G Frederich; Elias, William J; Laws, Edward R; Dhawan, Vijay; Stoessl, A Jon; Matcham, James; Coffey, Robert J; Traub, Michael
2006 Mar;59(3):459-466, Annals of neurology
OBJECTIVE: Glial cell line-derived neurotrophic factor (GDNF) exerts potent trophic influence on midbrain dopaminergic neurons. This randomized controlled clinical trial was designed to confirm initial clinical benefits observed in a small, open-label trial using intraputamenal (Ipu) infusion of recombinant human GDNF (liatermin). METHODS: Thirty-four PD patients were randomized 1 to 1 to receive bilateral continuous Ipu infusion of liatermin 15 microg/putamen/day or placebo. The primary end point was the change in Unified Parkinson Disease Rating Scale (UPDRS) motor score in the practically defined off condition at 6 months. Secondary end points included other UPDRS scores, motor tests, dyskinesia ratings, patient diaries, and (18)F-dopa uptake. RESULTS: At 6 months, mean percentage changes in 'off' UPDRS motor score were -10.0% and -4.5% in the liatermin and placebo groups, respectively. This treatment difference was not significant (95% confidence interval, -23.0 to 12.0, p = 0.53). Secondary end point results were similar between the groups. A 32.5% treatment difference favoring liatermin in mean (18)F-dopa influx constant (p = 0.019) was observed. Serious, device-related adverse events required surgical repositioning of catheters in two patients and removal of devices in another. Neutralizing antiliatermin antibodies were detected in three patients (one on-study and two in the open-label extension). INTERPRETATION: Liatermin did not confer the predetermined level of clinical benefit to patients with PD despite increased (18)F-dopa uptake. It is uncertain whether technical differences between this trial and positive open-label studies contributed in any way this negative outcome
— id: 96360, year: 2006, vol: 59, page: 459, stat: Journal Article,

Perfusion magnetic resonance imaging predicts patient outcome as an adjunct to histopathology: a second reference standard in the surgical and nonsurgical treatment of low-grade gliomas
Law, Meng; Oh, Sarah; Johnson, Glyn; Babb, James S; Zagzag, David; Golfinos, John; Kelly, Patrick J
2006 Jun;58(6):1099-1107, Neurosurgery
OBJECTIVE: To determine whether relative cerebral blood volume (rCBV) can predict patient outcome, specifically tumor progression, in low-grade gliomas (LGGs) and thus provide a second reference standard in the surgical and postsurgical management of LGGs. METHODS: Thirty-five patients with histologically diagnosed LGGs (21 low-grade astrocytomas and 14 low-grade oligodendrogliomas and low-grade mixed oligoastrocytomas) were studied with dynamic susceptibility contrast-enhanced perfusion magnetic resonance imaging. Wilcoxon tests were used to compare patients in different response categories (complete response, stable, progressive, death) with respect to baseline rCBV. Log-rank tests were used to evaluate the association of rCBV with survival and time to progression. Kaplan-Meier time-to-progression curves were generated. Tumor volumes and CBV measurements were obtained at the initial examination and again at follow-up to determine the association of rCBV with tumor volume progression. RESULTS: Wilcoxon tests showed patients manifesting an adverse event (either death or progression) had significantly higher rCBV (P = 0.003) than did patients without adverse events (complete response or stable disease). Log-rank tests showed that rCBV exhibited a significant negative association with disease-free survival (P = 0.0015), such that low rCBV values were associated with longer time to progression. Kaplan-Meier curves demonstrated that lesions with rCBV less than 1.75 (n = 16) had a median time to progression of 4620 +/- 433 days, and lesions with rCBV more than 1.75 (n = 19) had a median time to progression of 245 +/- 62 days (P < 0.005). Lesions with low baseline rCBV (< 1.75) demonstrated stable tumor volumes when followed up over time, and lesions with high baseline rCBV (> 1.75) demonstrated progressively increasing tumor volumes over time. CONCLUSION: Dynamic susceptibility contrast-enhanced perfusion magnetic resonance imaging may be used to identify LGGs that are either high-grade gliomas, misdiagnosed because of sampling error at pathological examination or that have undergone angiogenesis in the progression toward malignant transformation. This suggests that rCBV measurements may be used as a second reference standard to determine the surgical management/risk-benefit equation and postsurgical adjuvant therapy for LGGs
— id: 65798, year: 2006, vol: 58, page: 1099, stat: Journal Article,

Resection of parietal lobe gliomas: incidence and evolution of neurological deficits in 28 consecutive patients correlated to the location and morphological characteristics of the tumor
Russell, Stephen M; Elliott, Robert; Forshaw, David; Kelly, Patrick J; Golfinos, John G
2005 Dec;103(6):1010-1017, Journal of neurosurgery
OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyrus. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance
— id: 61369, year: 2005, vol: 103, page: 1010, stat: Journal Article,

Neurosurgical robotics
Kelly, Patrick J
2002 ;49(2):136-158, Clinical neurosurgery
— id: 33631, year: 2002, vol: 49, page: 136, stat: Journal Article,

Subthalamic nucleus stimulation in patients with a prior pallidotomy
Mogilner, Alon Y; Sterio, Djordje; Rezai, Ali R; Zonenshayn, Martin; Kelly, Patrick J; Beric, Aleksandar
2002 Apr;96(4):660-665, Journal of neurosurgery
OBJECT: A substantial number of patients with Parkinson disease (PD) who have undergone unilateral stereotactic pallidotomy ultimately develop symptom progression, becoming potential candidates for further surgical treatment. Bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) has been shown to be effective in the treatment of a subset of patients with refractory PD. Microelectrode recording is performed to help localize the STN and guide final placement of the electrode. Potential alterations in physiological features of the STN after pallidotomy may complicate localization of this structure in this group of patients. METHODS: Bilateral STN DBS surgery guided by microelectrode recording was performed in six patients who had undergone previous unilateral pallidotomies. Physiologically obtained parameters of the STN, including trajectory length, mean firing rate, cell number, and cell density were calculated. These data were compared with those from the side without prior pallidotomy within each patient, as well as with those from our series of 49 subthalamic nuclei explored in 26 patients who had not undergone prior pallidotomy but who underwent bilateral STN stimulator placement. In all patients, analysis of STN cellular activity on the side ipsilateral to the pallidotomy demonstrated a lower mean firing frequency than on the contralateral, intact side. The physiological features on the intact side were not significantly different from those found in our series of patients who had not undergone prior pallidotomy. CONCLUSIONS: Physicians who perform STN surgery in patients with prior pallidotomy should be aware of the electrophysiological differences between the STN that had undergone pallidotomy and the one that had not, to avoid prolonging recording time to search for the typical STN. The implications of these findings for the current models of information processing in the basal ganglia are discussed
— id: 27569, year: 2002, vol: 96, page: 660, stat: Journal Article,

Volumetric stereotaxy and the supratentorial occipitosubtemporal approach in the resection of posterior hippocampus and parahippocampal gyrus lesions
Russell, Stephen M; Kelly, Patrick J
2002 May;50(5):978-988, Neurosurgery
OBJECTIVE: Resection of intracranial tumors in the posterior hippocampus and the parahippocampal gyrus can be associated with significant morbidity because of the parenchymal resection and the cortical retraction often required in gaining access to this infrequently explored region. With the use of image guidance, the occipitosubtemporal (OST) approach requires neither lateral cortical resection nor the placement of brain retractors to gain surgical access to the posterior hippocampus and the parahippocampal gyrus, and this approach is associated with a high rate of gross total tumor resection. METHODS: The computer-assisted volumetric stereotactic OST approach was used to resect 40 posterior hippocampus and parahippocampal gyrus tumors in 34 consecutive patients during an 8-year period. Patient, radiographic, and surgical outcome data were collected retrospectively. RESULTS: The series included operations in 25 men and 15 women, and the patients' average age was 40.3 years (range, 15-69 yr). Twenty-five of the 40 procedures were performed to remove lesions in the dominant hemisphere, and previous craniotomies for resection had been performed in 12 of 40 cases. In 38 of 40 cases, histopathological analysis revealed a glial neoplasm, and 50% of these tumors were high-grade lesions. Preoperatively, 23 patients were neurologically intact before 40 procedures, whereas visual field deficits were noted in 7 patients, mild hemiparesis was documented in 4 patients, and other neurological deficits were present in 9 patients. An excellent outcome (Glasgow Outcome Scale Grade 5) was noted after 38 (95%) of the 40 computer-assisted volumetric stereotactic OST procedures. Permanent postoperative hemiparesis (Glasgow Outcome Scale Grade 4) occurred after one procedure, and a second patient, despite being neurologically unchanged postoperatively and despite having had an optimal tumor resection, died on postoperative Day 33 (Glasgow Outcome Scale Grade 1). Complete resection of the preoperatively defined tumor volume was noted on postoperative gadolinium-enhanced magnetic resonance imaging examinations after 39 (97.5%) of the 40 procedures. The average duration of clinical follow-up was 15.9 months (range, 0.5-67 mo). CONCLUSION: We think that the OST approach is well suited to the resection of tumors in the posterior hippocampus and the parahippocampal gyrus. By allowing the neurosurgeon to avoid unnecessary brain resection and retraction, this approach reduces the risk of injury to important lateral temporal and occipital lobe cortex and tracts. In addition, the resection of a posterior hippocampus or parahippocampal gyrus mass with the OST approach relieves temporal horn entrapment. Computer-assisted volumetric stereotaxy helps the neurosurgeon to maintain precise spatial and anatomic orientation and accurately delineates the margin between the tumor and the surrounding neural tissue
— id: 33633, year: 2002, vol: 50, page: 978, stat: Journal Article,

Neurophysiological refinement of subthalamic nucleus targeting
Sterio, Djordje; Zonenshayn, Martin; Mogilner, Alon Y; Rezai, Ali R; Kiprovski, Kiril; Kelly, Patrick J; Beric, Aleksandar
2002 Jan;50(1):58-67, Neurosurgery
OBJECTIVE: Advances in image-guided stereotactic surgery, microelectrode recording techniques, and stimulation technology have been the driving forces behind a resurgence in the use of functional neurosurgery for the treatment of movement disorders. Despite the dramatic effects of deep brain stimulation (DBS) techniques in ameliorating the symptoms of Parkinson's disease, many critical questions related to the targeting, effects, and mechanisms of action of DBS remain unanswered. In this report, we describe the methods used to localize the subthalamic nucleus (STN) and we present the characteristics of encountered cells. METHODS: Twenty-six patients with idiopathic Parkinson's disease underwent simultaneous, bilateral, microelectrode-refined, DBS electrode implantation into the STN. Direct and indirect magnetic resonance imaging-based anatomic targeting was used. Cellular activity was analyzed for various neurophysiological parameters, including firing rates and interspike intervals. Physiological targeting confirmation was obtained by performing macrostimulation through the final DBS electrode. RESULTS: The average microelectrode recording time for each trajectory was 20 minutes, with a mean of 5.2 trajectories/patient. Typical trajectories passed through the anterior thalamus, zona incerta/fields of Forel, STN, and substantia nigra-pars reticulata. Each structure exhibited a characteristic firing pattern. In particular, recordings from the STN exhibited an increase in background activity and an irregular firing pattern, with a mean rate of 47 Hz. The mean cell density was 5.6 cells/mm, with an average maximal trajectory length of 5.3 mm. Macrostimulation via the DBS electrode yielded mean sensory and motor thresholds of 4.2 and 5.7 V, respectively. CONCLUSION: The principal objectives of microelectrode recording refinement of anatomic targeting are precise identification of the borders of the STN and thus determination of its maximal length. Microelectrode recording also allows identification of the longest and most lateral segment of the STN, which is our preferred target for STN DBS electrode implantation. Macrostimulation via the final DBS electrode is then used primarily to establish the side effect profile for postoperative stimulation. Microelectrode recording is a helpful targeting adjunct that will continue to facilitate our understanding of basal ganglion physiological features
— id: 33634, year: 2002, vol: 50, page: 58, stat: Journal Article,

Complications of deep brain stimulation surgery
Beric A; Kelly PJ; Rezai A; Sterio D; Mogilner A; Zonenshayn M; Kopell B
2001 ;77(1-4):73-78, Stereotactic & functional neurosurgery
Although technological advances have reduced device-related complications, DBS surgery still carries a significant risk of transient and permanent complications. We report our experience in 86 patients and 149 DBS implants. Patients with Parkinson's disease, essential tremor and dystonia were treated. There were 8 perioperative, 8 postoperative, 9 hardware-related complications and 4 stimulation-induced side effects. Only 5 patients (6%) sustained some persistent neurological sequelae, however, 26 of the 86 patients undergoing 149 DBS implants in this series experienced some untoward event with the procedure. Although there were no fatalities or permanent severe disabilities encountered, it is important to extend the informed consent to include all potential complications
— id: 33632, year: 2001, vol: 77, page: 73, stat: Journal Article,

Stereotactic biopsy aided by a computer graphics workstation: Experience with 200 consecutive cases - Commentary
Kelly, PJ
2001 DEC ;56(6):371-372, Surgical neurology
— id: 98266, year: 2001, vol: 56, page: 371, stat: Journal Article,

Robot-assisted microsurgery: a feasibility study in the rat
Le Roux PD; Das H; Esquenazi S; Kelly PJ
2001 Mar;48(3):584-589, Neurosurgery
OBJECTIVE: Telerobotic surgery is a novel technology that can improve a surgeon's manual dexterity as well as the results achieved with microsurgical procedures. METHODS: A prototype Robot-Assisted MicroSurgery (RAMS) microdexterity enhancement system developed by the Jet Propulsion Laboratory and MicroDexterity Systems, Inc., was tested in 10 rats. Carotid arteriotomies were created and closed using either the RAMS system or conventional microsurgical techniques. The time required, the technical quality (vessel patency and suture line integrity), the error rate, and subjective difficulty were compared. RESULTS: All procedures were successfully completed using the RAMS system to manipulate the vessel but not to hold the needle or place the sutures. The precision, technical quality, and error rate of telerobotic surgery were similar to those of conventional techniques. However, the use of the RAMS system was associated with a twofold increase in the length of the procedure. CONCLUSION: Surgery using a microdexterity enhancement system, or RAMS prototype, is feasible. With further development, such as a stereotelevisualization and haptic feedback system, this system could be used for telerobotic surgery in neurosurgical practice
— id: 26768, year: 2001, vol: 48, page: 584, stat: Journal Article,

Transcranial electrical motor evoked potential monitoring for brain tumor resection
Zhou HH; Kelly PJ
2001 May;48(5):1075-1080, Neurosurgery
OBJECTIVE: This study was designed to examine whether transcranial electrical motor evoked potential (MEP) monitoring is safe, feasible, and valuable for brain tumor surgery. METHODS: Fifty consecutive patients undergoing brain tumor resection were studied, using nitrous oxide/propofol anesthesia. MEPs were continuously recorded throughout surgery, using a Sentinel 4 evoked potential system (Axon Systems, Inc., Hauppauge, NY). The MEPs were elicited by transcranial electrical stimulation (train of 5; stimulation rate, 0.5-2 Hz; square wave pulse with a time constant of 0.5 ms; stimulation intensity, 40-160 mA) through spiral electrodes placed over the primary motor cortex and were recorded by needle electrodes inserted into the contralateral orbicularis oris, biceps, abductor pollicis brevis, and anterior tibialis muscles. When MEP amplitudes decreased by more than 50%, MEP stimulation was repeated, with increased stimulation intensity, and MEP changes were reported to the surgeon. The motor function of each patient was examined before and after surgery, using a reproducible scale. The relationship between MEP amplitude decreases and worsening motor status was analyzed using linear regression. RESULTS: Preoperative neurological examinations revealed mild to moderate motor deficits (2/5 to 4/5) for 38% of patients (19 of 50 patients). Most of the patients (96%) exhibited recordable baseline MEPs. Persistent MEP decreases of more than 50% were noted for eight patients (16%) (11 muscles). The MEPs were completely abolished in two patients (three muscles). The degree of postoperative worsening of motor status was correlated with the degree of intraoperative MEP amplitude reduction (r = -0.864; P < 0.001). CONCLUSION: Persistent intraoperative MEP reductions of more than 50% were associated with postoperative motor deficits. The degree of MEP amplitude reduction was correlated with postoperative worsening of motor status. Transcranial electrical MEP monitoring is feasible, safe, and valuable for brain tumor surgery
— id: 20690, year: 2001, vol: 48, page: 1075, stat: Journal Article,

Stereotactic surgery: what is past is prologue
Kelly PJ
2000 Jan;46(1):16-27, Neurosurgery
Two old and simple simple concepts, a three-dimensional positioning stage and a coordinate system, were combined in 1906 to create a new one: the stereotactic method. For 25 years, it found little application until it was rediscovered for investigations in small animals. After the first human subcortical stereotactic procedure was performed in 1947, stereotactic methods found greatest application in the placement of subcortical lesions in the treatment of movement disorders. Rapid advances in the development of instrumentation, methods, and understanding of human neuroanatomy and neurophysiology resulted. However, a dormant period followed the introduction of L-dopa in 1968. The advent of computer-based medical imaging applied to the stereotactic method encouraged adaptation of stereotactic methods to the management of intracranial tumors, the rapid development of new surgical hardware, and the rediscovery of old methods and evolution of new ones for the treatment of movement disorders. In addition, the incorporation of computer systems as stereotactic surgical instruments further increased the capabilities of stereotactic methods. Radiosurgical applications increased with the proliferation of gamma units and the development of linear accelerator-based radiosurgical methods. Computers are used to fuse and reformat imaging databases for surgical planning, simulation, and frameless stereotactic intraoperative guidance. As a result, surgical procedures have become more effective in meeting preoperative goals and less invasive. Low-cost, high-speed, microprocessor-based workstation computers and intuitive user interfaces have increased the acceptance into mainstream neurosurgery. It is anticipated that a significant portion of neurosurgery, and probably most surgical procedures in general, will comprise computer-based interventions guided by volumetric imaging-defined data sets acquired preoperatively or by intraoperative imaging systems. The stereotactic surgery of the future may employ all or a combination of the following technologies: frameless stereotactic surgery, robotic technology, microrobotic dexterity enhancement, and telepresence robotics
— id: 11874, year: 2000, vol: 46, page: 16, stat: Journal Article,

Comparison of anatomic and neurophysiological methods for subthalamic nucleus targeting [In Process Citation]
Zonenshayn M; Rezai AR; Mogilner AY; Beric A; Sterio D; Kelly PJ
2000 Aug;47(2):282-292, Neurosurgery
OBJECTIVE: The subthalamic nucleus (STN) has recently become the surgical target of choice for the treatment of medically refractory idiopathic Parkinson's disease. A number of anatomic and physiological targeting methods have been used to localize the STN. We retrospectively reviewed the various anatomic targeting methods and compared them with the final physiological target in 15 patients who underwent simultaneous bilateral STN implantation of deep brain stimulators. METHODS: The x, y, and z coordinates of our localizing techniques were analyzed for 30 STN targets. Our final targets, as determined by single-cell microelectrode recording, were compared with the following: 1) targets selected on coronal magnetic resonance inversion recovery and T2-weighted imaging sequences, 2) the center of the STN on a digitized scaled Schaltenbrand-Wahren stereotactic atlas, 3) targeting based on a point 13 mm lateral, 4 mm posterior, and 5 mm inferior to the midcommissural point, and 4) a composite target based on the above methods. RESULTS: All anatomic methods yielded targets that were statistically significantly different (P < 0.001) from the final physiological targets. The average distance error between the final physiological targets and the magnetic resonance imaging-derived targets was 2.6 +/- 1.3 mm (mean +/- standard deviation), 1.7 +/- 1.1 mm for the atlas-based method, 1.5 +/- 0.8 mm for the indirect midcommissural method, and 1.3 +/- 1.1 mm for the composite method. Once the final microelectrode-refined target was determined on the first side, the final target for the contralateral side was 1.3 +/- 1.2 mm away from its mirror image. CONCLUSION: Although all anatomic targeting methods provide accurate STN localization, a combination of the three methods offers the best correlation with the final physiological target. In our experience, direct magnetic resonance targeting was the least accurate method
— id: 11550, year: 2000, vol: 47, page: 282, stat: Journal Article,

Microelectrode recording during posteroventral pallidotomy: impact on target selection and complications
Alterman RL; Sterio D; Beric A; Kelly PJ
1999 Feb;44(2):315-321, Neurosurgery
OBJECTIVE: To assess the practical usefulness of single-cell microelectrode recording (MER) when performing posteroventral pallidotomy. METHODS: A retrospective comparison of the initial, magnetic resonance imaging-derived coordinates of the pallidotomy target to the final, MER-refined lesion coordinates in 132 consecutive pallidotomies was conducted. The time required to perform the procedure and the surgical complications are reported. RESULTS: MER led to targeting changes in 98% of the cases. In 12%, the MER-refined target was more than 4 mm from the original, image-guided site, which is a targeting error that could adversely affect outcome. Although all components of targeting were affected by MER, laterality and depth were impacted most. The ventral border of the globus pallidus pars interna was located within 1 mm of the magnetic resonance imaging-selected target in only 40% of the cases. On average, only 2.2 MER trajectories were required to perform pallidotomy. During the last 3 years of our study, 85% of the procedures were performed with one or two trajectories. The mean operating time of the operations performed during the last 3 years was 2 hours and 12 minutes. The incidence of intracerebral hemorrhage in our series (1.5%) was no higher than that reported for other large series of stereotactic procedures. No patient suffered an optic tract injury. CONCLUSION: MER provides important targeting information for performing pallidotomy. In particular, the micrometric delineation of the ventral border of the globus pallidus pars interna permits safe lesioning of the posteroventral region of the globus pallidus pars interna with little risk of visual field deficit. These data can be obtained efficiently and without increased surgical risk
— id: 25189, year: 1999, vol: 44, page: 315, stat: Journal Article,

Glial neoplasms: dynamic contrast-enhanced T2*-weighted MR imaging
Knopp EA; Cha S; Johnson G; Mazumdar A; Golfinos JG; Zagzag D; Miller DC; Kelly PJ; Kricheff II
1999 Jun;211(3):791-798, Radiology
PURPOSE: To evaluate the role of T2*-weighted echo-planar perfusion imaging by using a first-pass gadopentetate dimeglumine technique to determine the association of magnetic resonance (MR) imaging-derived cerebral blood volume (CBV) maps with histopathologic grading of astrocytomas and to improve the accuracy of targeting of stereotactic biopsy. MATERIALS AND METHODS: MR imaging was performed in 29 patients by using a first-pass gadopentetate dimeglumine T2*-weighted echo-planar perfusion sequence followed by conventional imaging. The perfusion data were processed to obtain a color map of relative regional CBV. This information formed the basis for targeting the stereotactic biopsy. Relative CBV values were computed with a nondiffusible tracer model. The relative CBV of lesions was expressed as a percentage of the relative CBV of normal white matter. The maximum relative CBV of each lesion was correlated with the histopathologic grading of astrocytomas obtained from samples from stereotactic biopsy or volumetric resection. RESULTS: The maximum relative CBV in high-grade astrocytomas (n = 26) varied from 1.73 to 13.7, with a mean of 5.07 +/- 2.79 (+/- SD), and in the low-grade cohort (n = 3) varied from 0.92 to 2.19, with a mean of 1.44 +/- 0.68. This difference in relative CBV was statistically significant (P < .001; Student t test). CONCLUSION: Echo-planar perfusion imaging is useful in the preoperative assessment of tumor grade and in providing diagnostic information not available with conventional MR imaging. The areas of perfusion abnormality are invaluable in the precise targeting of the stereotactic biopsy
— id: 6128, year: 1999, vol: 211, page: 791, stat: Journal Article,

Angiographic abnormalities in progressive multifocal leukoencephalopathy: an explanation based on neuropathologic findings
Nelson PK; Masters LT; Zagzag D; Kelly PJ
1999 Mar;20(3):487-494, AJNR. American journal of neuroradiology
BACKGROUND AND PURPOSE: Progressive multifocal leukoencephalopathy (PML) is typically occult at angiography and fails to enhance on MR images. After observing angiographic abnormalities characterized by arteriovenous shunting and pathologic parenchymal blush in patients with AIDS-related PML, often in the absence of contrast enhancement on MR images, we hypothesized that there might be distinct changes in the cerebral microvasculature that account for the reduction in vascular transit time (arteriovenous shunting) in the absence of blood-brain barrier dysfunction. METHODS: The imaging studies and neuropathologic specimens of six patients with biopsy-proved PML were reviewed retrospectively. In all patients contrast-enhanced MR imaging and CT, followed by cerebral angiography, were performed before stereotactically directed biopsy. The angiograms were evaluated for the presence of vascular displacement, pathologic parenchymal blush, arteriovenous shunting, and neovascularity. The CT and MR studies were reviewed for the presence of enhancement of the PML lesions. Biopsy specimens were examined for the presence of necrosis, perivascular inflammation, and neovascularity. RESULTS: All patients had oligodendrocytic intranuclear inclusions diagnostic of PML, together with perivascular inflammation and neovascularity to a varying extent; no other neuropathologic processes were identified. Angiographic abnormalities, characterized by a pathologic parenchymal blush and arteriovenous shunting, were identified in four of the six patients. In only one of these cases, however, was abnormal enhancement identified on cross-sectional imaging studies (MR and CT), and this patient had florid perivascular inflammatory infiltrates histologically. CONCLUSION: The pathologic parenchymal blush and arteriovenous shunting seen angiographically in some patients with PML reflect small-vessel proliferation and perivascular inflammatory changes incited by the presence of the JC virus in infected oligodendrocytes
— id: 6100, year: 1999, vol: 20, page: 487, stat: Journal Article,

Pallidotomy technique and results: the New York University experience
Alterman RL; Kelly PJ
1998 Apr;9(2):337-343, Neurosurgery clinics of North America
The authors relate the New York University experience with 171 pallidotomies performed on 160 consecutive patients over a 6-year period. Details of their patient selection criteria, operative technique, preliminary clinical results, and surgical complications are reported. They conclude that unilateral posteroventral pallidotomy is a safe and effective treatment for a subset of Parkinson's disease patients who suffer with rigidity, bradykinesia, tremor, and L-dopa-induced dyskinesia. Patients with Parkinson's Plus syndromes can be definitively identified with positron emission tomography and do not improve with pallidotomy. The routine performance of bilateral pallidotomy remains controversial
— id: 7482, year: 1998, vol: 9, page: 337, stat: Journal Article,

Nocardia abscess of the choroid plexus: clinical and pathological case report
Mogilner A; Jallo GI; Zagzag D; Kelly PJ
1998 Oct;43(4):949-952, Neurosurgery
OBJECTIVE: Cerebral Nocardia abscesses are rare, accounting for approximately 1 to 2% of all cerebral abscesses. Prompt aggressive surgical treatment involving craniotomy and excision of these lesions has been advocated by many authors, because these lesions have significantly higher morbidity and mortality rates than do most other cerebral abscesses. We report an atypical presentation of cerebral nocardiosis localized to the choroid plexus of the lateral ventricle. CLINICAL PRESENTATION: A 56-year-old man presented with a 3-week history of fever, cough, and progressive headache and an ensuing 3-day history of progressive lethargy, confusion, and gait ataxia. Radiographic studies demonstrated a loculated contrast-enhancing left lateral ventricular lesion with significant perilesional parenchymal edema that was thought preoperatively to be a neoplasm. INTERVENTION: The patient underwent a craniotomy for resection of the lesion. Intraoperatively, a reddish gray lesion with purulent exudate was encountered within the left lateral ventricle intimately adherent to the choroid plexus as well as to the ependyma and subependymal veins. A frozen section demonstrated an organizing abscess wall. The lesion was resected in its entirety, and multiple cultures were sent for analysis. CONCLUSION: Microbiology cultures grew Nocardia asteroides. A course of intravenous antibiotics was started, which included trimethoprim-sulfamethoxazole, amikacin, and ceftriaxone. Two weeks after surgery, at the time of discharge, the patient's neurological status had improved considerably. Although Nocardia abscesses have been documented to occur throughout the central nervous system, the presentation of a lesion confined to the choroid plexus of the lateral ventricle with significant parenchymal edema is unusual and demonstrates that Nocardia abscesses must be considered in the differential diagnosis of a contrast-enhancing intraventricular mass lesion involving the choroid plexus
— id: 7691, year: 1998, vol: 43, page: 949, stat: Journal Article,

Computer-assisted image-guided surgery using the Regulus Navigator
Rousu JS; Kohls PE; Kall B; Kelly PJ
1998 ;50(1-4 Pt 2):103-109, Studies in health technology & informatics
The term 'frameless image-guided surgery' has become as well-known to surgeons as computerized tomography or operating room microscope over the past several years. The technologies behind this new surgery option include robotic arms, infra-red camera arrays (1D and 2D), ultrasound, robotic microscopes and magnetic field digitizers. The authors have shown the magnetic field technology incorporated in the Regulus Navigator to be a viable, accurate surgeon's tool by first integrating a conventional framed device and magnetic field frameless device, then advancing to the frameless device alone. During surgery a patient's anatomy is first registered to preoperatively acquired radiological data. Surgical instruments are tracked on interactive CT/MRI displays as the surgeon locates his point or volume-in-space within the surgical field and uses his own procedure/technique of choice for surgical treatment. A clinical trial of 221 patients showed an overall mean accuracy of 2.56 mm with a standard deviation of 1.15 mm for intraoperative registration. Major concerns of utilizing magnetic field technology in the operating room, such as interference from surrounding metallic objects and equipment, were proven manageable while maintaining acceptable accuracy
— id: 33697, year: 1998, vol: 50, page: 103, stat: Journal Article,

Pallidal targeting with the COMPASS system
Alterman RL; Kall B; Beric A; Sterio D; Kelly PJ
1997 ;69(1-4 Pt 2):69-72, Stereotactic & functional neurosurgery
The authors describe their initial experience with the new pallidotomy targeting software for the COMPASS system. As COMPASS permits window and contrast settings to be changed at any time, multiple imaging modalities can be employed for targeting. This feature allowed the incorporation of fast-spin echo/inversion recovery (FSE/IR) magnetic resonance images (MRI) into the planning protocol. COMPASS has now been employed for 33 consecutive pallidotomies over the last year (July 96-June 97). A statistically significant reduction in the number of microelectrode recording trajectories required to physiologically localize sensorimotor globus pallidus interna (GPi) is noted in these cases as compared to the 41 cases performed in the previous year with a different computer planning system. The authors conclude that the COMPASS system accurately and efficiently targets the internal pallidum when FSE/IR MRI is employed. Nevertheless, pallidotomy should not be performed without neurophysiological localization
— id: 7296, year: 1997, vol: 69, page: 69, stat: Journal Article,

Selection criteria for unilateral posteroventral pallidotomy
Alterman RL; Kelly P; Sterio D; Fazzini E; Eidelberg D; Perrine K; Beric A
1997 ;68(5):18-23, Acta neurochirurgica. Supplementum
In an attempt to refine the indications for posteroventral pallidotomy (PVP) the authors instituted strict selection criteria which are based on the experience gained from the first 60 pallidotomy patients treated at their institution. In addition to clinical evaluation, all pallidotomy candidates undergo neuropsychological testing and 18F-fluoro-deoxyglucose utilization positron emission tomography (FDG/PET). The data from which these criteria were developed are presented as are early clinical results. The authors demonstrate that these criteria enhance the efficacy of the procedure by assuring therapeutic response and reducing the incidence of post-operative dementia. Their indications and contraindications for pallidotomy are discussed
— id: 25191, year: 1997, vol: 68, page: 18, stat: Journal Article,

Left-right differences in motor thresholds after stimulation of the globus pallidus before pallidotomy
Beric A; Sterio D; Dogali M; Kelly P
1997 Aug;63(2):159-162, Journal of neurology neurosurgery & psychiatry
Left-right upper limb motor threshold differences were found after electrical stimulation of the globus pallidus administered as a neuroprotective measure to avoid lesioning of the internal capsule during stereotactic pallidotomy for treatment of Parkinson's disease. Left sided stimulation resulted in lower thresholds in right handed patients compared with left handed patients. These differences were significant in women, but no significant differences were found in men. In patients undergoing bilateral pallidotomy, the stimulation produced more significant left-right motor threshold differences. In the absence of known sex-related anatomical left-right corticospinal tract differences, the variability was the result of spinal excitability modulations most likely related to handedness
— id: 7113, year: 1997, vol: 63, page: 159, stat: Journal Article,

Metabolic correlates of pallidal neuronal activity in Parkinson's disease
Eidelberg D; Moeller JR; Kazumata K; Antonini A; Sterio D; Dhawan V; Spetsieris P; Alterman R; Kelly PJ; Dogali M; Fazzini E; Beric A
1997 Aug;120 ( Pt 8)(2):1315-1324, Brain
We have used [18F]fluorodeoxyglucose and PET to identify specific metabolic covariance patterns associated with Parkinson's disease and related disorders previously. Nonetheless, the physiological correlates of these abnormal patterns are unknown. In this study we used PET to measure resting state glucose metabolism in 42 awake unmedicated Parkinson's disease patients prior to unilateral stereotaxic pallidotomy for relief of symptoms. Spontaneous single unit activity of the internal segment of the globus pallidus (GPi) was recorded intraoperatively in the same patients under identical conditions. The first 24 patients (Group A) were scanned on an intermediate resolution tomograph (full width at half maximum, 8 mm); the subsequent 18 patients (Group B) were scanned on a higher resolution tomograph (full width half maximum, 4.2 mm). We found significant positive correlations between GPi firing rates and thalamic glucose metabolism in both patient groups (Group A: r = 0.41, P < 0.05; Group B: r = 0.69, P < 0.005). In Group B, pixel-based analysis disclosed a significant focus of physiological-metabolic correlation involving the ventral thalamus and the GPi (statistical parametric map: P < 0.05, corrected). Regional covariance analysis demonstrated that internal pallidal neuronal activity correlated significantly (r = 0.65, P < 0.005) with the expression of a unique network characterized by covarying pallidothalamic and brainstem metabolic activity. Our findings suggest that the variability in pallidal neuronal firing rates in Parkinson's disease patients is associated with individual differences in the metabolic activity of efferent projection systems
— id: 18381, year: 1997, vol: 120 ( Pt 8), page: 1315, stat: Journal Article,

Magnetoencephalographic mapping: basic of a new functional risk profile in the selection of patients with cortical brain lesions
Hund M; Rezai AR; Kronberg E; Cappell J; Zonenshayn M; Ribary U; Kelly PJ; Llinas R
1997 May;40(5):936-942, Neurosurgery
OBJECTIVE: Surgical management of cortical lesions adjacent to or within the eloquent cerebral cortex requires a critical risk: benefit analysis of the procedure before intervention. This study introduced a measure of surgical risk, based on preoperative magnetoencephalographic (MEG) sensory and motor mapping, and tested its value in predicting surgical morbidity. METHODS: Forty patients (21 men and 19 women; mean age, 36.5 yr) with cortical lesions (12 arteriovenous malformations and 28 tumors) in the vicinity of the sensorimotor cortex were classified into high-, medium-, or low-risk categories by using the MEG-defined functional risk profile (FRP). This was based on the minimal distance between the lesion margin and the sensory and motor MEG sources, superimposed on a magnetic resonance imaging scan. Case management decisions were based on the MEG mapping-derived FRP in combination with biopsy pathological findings, radiographic findings, and anatomic characteristics of the lesion. A recently developed protocol was used to transform MEG source locations into the stereotactic coordinate system. This procedure provided intraoperative access to MEG data in combination with stereotactic anatomic data displays routinely available on-line during surgery. RESULTS: It was determined that 11 patients diagnosed as having gliomas had high FRPs. The margin of the lesion was less than 4 mm from the nearest MEG dipole or involved the central sulcus directly. A nonoperative approach was used for six patients of this group, based on the MEG mapping-derived FRP. In the group with arteriovenous malformations, 6 of 12 patients with high or medium FRPs underwent nonoperative therapy. The remaining 28 patients, whose lesions showed satisfactory FRPs, underwent uneventful lesion resection, without postoperative neurological deficits. CONCLUSION: Our results suggest that MEG mapping-derived FRPs can serve as powerful tools for use in presurgical planning and during surgery
— id: 9882, year: 1997, vol: 40, page: 936, stat: Journal Article,

Tenascin-C expression in the cyst wall and fluid of human brain tumors correlates with angiogenesis
Jallo GI; Friedlander DR; Kelly PJ; Wisoff JH; Grumet M; Zagzag D
1997 Nov;41(5):1052-1059, Neurosurgery
OBJECTIVE: Tenascin-C (TN) is an extracellular matrix glycoprotein with a characteristic six-armed structure. The aim of this study was to determine whether the concentration of TN in the cyst fluid of brain tumors can be used as a marker for angiogenesis and glioma grade. METHODS: We investigated the expression of TN in the cyst wall and cyst fluid of human brain tumors by immunohistochemistry, immunoprecipitation, and immunoblotting. The tumors included 12 astrocytomas (5 glioblastoma multiforme tumors, 1 anaplastic astrocytoma, 1 low-grade astrocytoma, 4 juvenile pilocytic astrocytomas, and 1 mixed glioma), 2 dysembryoplastic neuroepithelial tumors, 3 craniopharyngiomas, 2 ependymomas, 2 metastatic carcinomas, 3 arachnoid cysts, 1 glial ependymal cyst, and 1 inflammatory cyst. RESULTS: We detected no expression of TN in the cyst fluids of the ependymomas, craniopharyngiomas, and nonpilocytic low-grade astrocytoma. By contrast, TN was detected in the cyst fluids of all the other tumors. Results of quantitative immunoblotting using a PhosphorImager unit (Molecular Dynamics, Sunnyvale, CA) revealed that, on average, a 5-fold higher signal was observed in the glioblastoma multiforme tumors as compared with the anaplastic astrocytoma, and a 10-fold higher signal as compared with the mixed glioma, juvenile pilocytic astrocytomas, and dysembryoplastic neuroepithelial tumors. Results of TN immunohistochemistry in the astrocytomas correlated with glioma grade, with stronger staining of the hyperplastic vessels and tumor cells being observed in higher grade gliomas. No TN immunoreactivity was detected in the walls of the ependymomas, arachnoid cysts, and glial ependymal cyst that lack hyperplastic vessels, and minimal TN immunoreactivity was observed in the perivascular gliotic rim of the craniopharyngiomas. No TN was detected in the cyst fluid of these cystic processes. CONCLUSION: The presence of TN in and around the hyperplastic vessels and tumor cells present in the cyst walls of astrocytomas and its deposition in the intratumoral cyst fluid in which angiogenic factors have been detected further suggests a role for TN as an angiogenic modulator. These preliminary results suggest that immunodetection of TN in the tumor cyst fluid may indicate tumor type and grade
— id: 9349, year: 1997, vol: 41, page: 1052, stat: Journal Article,

Preoperative indicators of clinical outcome following stereotaxic pallidotomy
Kazumata K; Antonini A; Dhawan V; Moeller JR; Alterman RL; Kelly P; Sterio D; Fazzini E; Beric A; Eidelberg D
1997 Oct;49(4):1083-1090, Neurology
We assessed the utility of preoperative clinical assessment and functional brain imaging with 18F-fluorodeoxyglucose (FDG) and positron emission tomography (PET) in predicting the clinical outcome of stereotaxic pallidotomy for the treatment of advanced Parkinson's disease (PD). Twenty-two PD patients undergoing posteroventral pallidotomy were assessed preoperatively with the Core Assessment Program for Intracerebral Transplantation (CAPIT) ratings measured on and off levodopa; quantitative FDG/PET was also performed before surgery. Preoperative clinical and metabolic measurements were correlated with changes in off-state CAPIT ratings determined 3 months after surgery. Clinical outcome following pallidotomy was also correlated with intraoperative measures of spontaneous pallidal single-unit activity as well as postoperative MRI measurements of lesion volume and location. We found that unilateral pallidotomy resulted in variable clinical improvement in off-state CAPIT scores for the contralateral limbs (mean change 30.9 +/- 15.5%). Postoperative MRI revealed that pallidotomy lesions were comparable in location and volume across the patients. Clinical outcome following surgery correlated significantly with preoperative measures of CAPIT score change with levodopa administration (r = 0.60, p < 0.005) and with preoperative FDG/PET measurements of lentiform glucose metabolism (r = 0.71, p < 0.0005). Operative outcome did not correlate with intraoperative measures of spontaneous pallidal neuronal firing rate. We conclude that preoperative measurements of lentiform glucose metabolism and levodopa responsiveness may be useful indicators of motor improvement following pallidotomy. Both preoperative quantitative measures, either singly or in combination, may be helpful in selecting optimal candidates for surgery
— id: 25190, year: 1997, vol: 49, page: 1083, stat: Journal Article,

Neurological surgery at New York University Medical Center
Kelly PJ
1997 Apr;40(4):814-821, Neurosurgery
New york university Medical Center underwent a complex evolution in a rapidly growing and dynamic city. Care for the hospital-based poor resulted in international preeminence in surgical techniques. Neurosurgery at New York University has also evolved to meet the demands of the Medical Center and the community. Developments in high technology surgery and telecommunications will provide an international resource and trainees who are prepared to face the challenges of practice in the next century
— id: 7178, year: 1997, vol: 40, page: 814, stat: Journal Article,

Stereotactic procedures for molecular neurosurgery
Kelly PJ
1997 Mar;144(1):157-159, Experimental neurology
Stereotactic methods combined with modern computing power and imaging data bases provide powerful options for molecular neurosurgery. Point-in-space and volumetric computer-assisted imaging-based tumor stereotactic procedures, whose original application for neuroablative treatment of movement disorders and for the biopsy, interstitial irradiation, and resection of brain tumors, can easily be modified for the preplanned and precise delivery of genetic agents to an imaging-defined anatomical target volume. These techniques would provide more uniform coverage and dose levels of the therapeutic material within the defined target structure
— id: 12359, year: 1997, vol: 144, page: 157, stat: Journal Article,

Reoperation for recurrent malignant gliomas: what are your indications?
Kelly PJ; Rappaport ZH; Bhagwati SN; Ushio Y; Vapalahti M; de Tribolet N
1997 Jan;47(1):39-42, Surgical neurology
— id: 12437, year: 1997, vol: 47, page: 39, stat: Journal Article,

Distribution of endogenous tumour necrosis factor alpha in gliomas
Maruno M; Kovach JS; Kelly PJ; Yanagihara T
1997 Jul;50(7):559-562, Journal of clinical pathology
AIMS: To determine the distribution and cellular origin of endogenous tumour necrosis factor alpha (TNF alpha) in the cellular components of human gliomas. METHODS: Frozen sections of 26 gliomas (four astrocytomas (As); two oligoastrocytomas (OA); one ansplastic astrocytoma (AA); one anaplastic oligoastrocytoma (AOA); 18 glioblastomas (GB)) were examined immunohistochemically using antihuman TNF alpha and anti-Leu-M5 (CD11c) antibodies. Additional studies with double immunohistocchemical procedures were performed with anti-glial fibrillary acidic protein and anti-neurofilament antibodies. RESULTS: Eighty per cent of the AA, AOA, and GB (16 of 20) had a positive reaction for TNF alpha, but only 17% of As and OA (one of six) were positive. Positive cells were seen in both the tumour tissue and adjacent brain tissues. TNF alpha protein was detected not only in the tumour cells but also in the endothelium of tumour vessels as well as reactive astrocytes and neurons. CONCLUSIONS: Endogenous TNF alpha is present in cells of various origins in glial tumours including tumour vessels; however, the role of TNF alpha may be different in different types of cells or altered microenvironment
— id: 33635, year: 1997, vol: 50, page: 559, stat: Journal Article,

Integration of functional brain mapping in image-guided neurosurgery
Rezai AR; Mogilner AY; Cappell J; Hund M; Llinas RR; Kelly PJ
1997 ;68:85-89, Acta neurochirurgica. Supplementum
Magnetoencephalographic (MEG) brain mapping was performed in 90 patients with lesions associated with eloquent sensorimotor cortex. The MEG-derived sensorimotor mapping information was utilised for risk analysis and planning. Subsequently, these patients underwent either stereotactic volumetric resection, stereotactic biopsy or non-surgical management of their lesions. In seventeen patients, the MEG sensorimotor localization was integrated into an operative stereotactic database (consisting of CT, MRI and digital angiography) to be used in an interactive fashion during computer-assisted stereotactic volumetric resection procedures. The spatial relationship between the MEG derived functional anatomy, the structural/radiological anatomy and the pathology could then be viewed simultaneously, thereby affording a safer trajectory and approach. In addition, the real-time availability of functional mapping information in an interactive fashion helped reduce surgical risk and minimise functional morbidity. All of these patients had resection of their lesions with no change in their neurological status. In conclusion, MEG is a non-invasive, accurate, and reproducible method for pre-operative assessment of patients with lesions associated with eloquent sensory and motor cortex. The interactive use of MEG functional mapping in the operating room can allow for a safer approach and resection of these eloquent cortex lesions
— id: 7245, year: 1997, vol: 68, page: 85, stat: Journal Article,

Electrical stimulation of the globus pallidus preceding stereotactic posteroventral pallidotomy
Beric A; Sterio D; Dogali M; Alterman R; Kelly P
1996 ;66(4):161-169, Stereotactic & functional neurosurgery
Physiological methods such as microelectrode recording of neuronal activity and electrical stimulation of target structures can improve the safety and efficacy of certain stereotactic surgeries. The globus pallidus (GP) was electrically stimulated in 136 patients with Parkinson's disease prior to unilateral posteroventral pallidotomy to identify functional areas and prevent deficits. We found that electrical stimulation of the GP elicited two principal responses: contractions of the contralateral hand and flashing lights. The mean voltage that evoked motor responses was 4.3 V (range 1.7-9.0 V), while higher intensity was necessary to elicit visual responses (mean 6.8 V; range 3.5-9.9 V). Contralateral tremor, speech impairment, paresthesias, and warm sensations were also elicited
— id: 7112, year: 1996, vol: 66, page: 161, stat: Journal Article,

Migration of brain tumor cells on extracellular matrix proteins in vitro correlates with tumor type and grade and involves alphaV and beta1 integrins
Friedlander DR; Zagzag D; Shiff B; Cohen H; Allen JC; Kelly PJ; Grumet M
1996 Apr 15;56(8):1939-1947, Cancer research
An important contributor to the malignancy of brain tumors is their ability to infiltrate the brain. Extracellular matrix molecules and cell adhesion molecules on cell surfaces play key roles in cell migration. In the present study, we used reaggregates of dissociated cells from freshly excised human brain tumors to analyze the migration of cells from human brain tumors of different types and grades on many different adhesion proteins adsorbed to glass substrates. Proteins were chosen based on their presence in normal or neoplastic nervous tissue, and included the extra-cellular matrix molecules fibronectin, collagens, fibrinogen, laminin, tenascin-C, thrombospondin, and the neuron-glia cell adhesion molecule, Ng-CAM. Cells from astrocytomas (n = 24) migrated on a variety of substrates, in contrast to cells from primitive neuroectodermal tumors cells (n=6), which only migrated well on laminin, fibronectin, or type IV collagen but not on the other substrates. Typically, migrating cells from astrocytomas of all grades had long, slender processes, were usually bipolar, and their cell bodies did not spread well on any substrate. Although there was variability in the migration of cells from astrocytomas of the same grade, cells from high-grade astrocytomas tended to migrate more extensively (42.3 +/- 4.7 micrometers/16 h: n = 16) than cells from lower grade astrocytomas (28.9 +/- 3.9 micrometers/16 h; P = 0.07; n = 8); the most striking differences were observed for collagen substrates, on which cells from lower grade astrocytomas migrated at very low levels (7.6 +/- 2 .6 micrometers/16 h) and cells from high-grade astrocytomas at higher levels (24.4 +/- 5.2 micrometers;P = 0.01). In contrast to primary cells from glioblastomas (n = 13), glioblastoma cell lines (n = 10) consistently spread on various substrates and migrated at high levels (69.5 +/- 7.6 versus 46.4 +/-5.7 micrometers/16 h; P = 0.03), in particular, on collagens (108.4 +/- 20.2 versus 28.0 +/- 6.1 micrometers/16 h; P= 0.001). Specific monoclonal antibodies to alphaV and beta1 integrin monomers completely inhibited the migration of astrocytoma cells on most substrates, suggesting that alphaV and beta1 integrins play a crucial role in brain tumor infiltration. These studies also suggest that although a large number of extracellular matrix molecules may promote tumor cell migration, disrupting the function of only a few tumor cell receptors may be critical for tumor infiltration in the brain
— id: 8091, year: 1996, vol: 56, page: 1939, stat: Journal Article,

Quantitative analysis of a noninvasive stereotactic image registration technique
Kall BA; Goerss SJ; Stiving SO; Davis DH; Kelly PJ
1996 ;66(1-3):69-74, Stereotactic & functional neurosurgery
Our group has developed and tested a noninvasive image registration technique that does not require a special imaging study following the application of a head frame or radiological markers on the patient. This registration method involves performing automatic alignment between segmented scalp reconstructions from CT or MRI fitted with are surfaces traced with the Regulus Navigator. This paper will present a quantitative analysis of this technique compared to other stereotactic and image-guided registration techniques. This noninvasive surface alignment technique has been found to be a viable, quick and accurate method of performing image-guided registration
— id: 33698, year: 1996, vol: 66, page: 69, stat: Journal Article,

Applications of the World Wide Web to neurosurgical practice [see comments]
Kim R; Kelly PJ
1996 Dec;39(6):1169-1181, Neurosurgery
OBJECTIVE: The objectives of the New York University (NYU) neurosurgery Web resource are the following: 1) to educate patients and families of patients who have neurosurgical problems, 2) to provide a forum for communication among neurosurgeons and other physicians, 3) to educate neurosurgeons, and 4) to provide neurosurgeons with resources for enhancing their practices. METHODS: The NYU neurosurgery Web resource resides on a Sun SparcStation 20, running Solaris 1.0 and National Center for Supercomputing Applications httpd 1.0. It is aimed at a broad audience that includes the general public as well as practicing neurosurgeons and other physicians. Accordingly, general information regarding a variety of neurosurgical problems is presented in easy-to-understand language. Material intended specifically for neurosurgeons, such as case discussions, is designed to stimulate discussion and encourage outside submissions. Interaction with the NYU faculty and residents may be accomplished by using electronic mail, file transfer protocol, and direct Web postings. Media in development include java applets and real-time video over the Internet. The uniform resource locator for the NYU neurosurgery Web site is 'http:/(/)mcns10.med.nyu.edu/'. RESULTS: The Web site has averaged 1800 accesses per month, and 5 to 10 electronic mail messages are received daily. Several patients for whom our faculty have held consultations over the Web have undergone surgery at NYU. The most popular areas of the Web site are the spinal surgery section and the brain tumors section. CONCLUSION: The ability to capitalize on the World Wide Web as a facile user is becoming an increasingly important skill for the modern neurosurgeon. In addition, Web sites published by neurosurgeons offer opportunities for communication and consultation that have previously been impossible
— id: 12464, year: 1996, vol: 39, page: 1169, stat: Journal Article,

The interactive use of magnetoencephalography in stereotactic image-guided neurosurgery
Rezai AR; Hund M; Kronberg E; Zonenshayn M; Cappell J; Ribary U; Kall B; Llinas R; Kelly PJ
1996 Jul;39(1):92-102, Neurosurgery
OBJECTIVE: To expand the use of magnetoencephalography (MEG) functional mapping in the operating room as well as preoperatively, a method of integrating the MEG sensorimotor mapping information into a stereotactic database, using computed tomographic scans, magnetic resonance imaging scans, and digital angiography, was developed. The combination of functional mapping and the stereotactic technique allows simultaneous viewing of the spatial relationship between the MEG-derived functional mapping, the radiological/structural anatomic characteristics, and the pathological abnormality. METHODS: MEG data were collected using a MAGNES II Biomagnetometer and were incorporated into the COMPASS frame-based and REGULUS frameless stereotactic systems. The transformation process, by calculating a translational vector and a rotation matrix, integrates functional and anatomic information that is then directly available intraoperatively in the stereotactic database. This procedure was employed in 10 patients undergoing computer-assisted stereotactic volumetric resections for lesions involving the sensorimotor cortex. The principles of coregistration and coordinate transformation are reviewed in the context of preoperative functional mapping. We introduce innovations to apply these techniques to intraoperative stereotactic systems. RESULTS: Tests of the accuracy of the intraoperative integration of functional information in patients and calibration phantoms indicated close agreement with earlier preoperative methods. The intraoperative availability of functional information was a significant aid to the surgeon because it provided more accurate information on the location of functional tissue than could be derived solely by radiological criteria. CONCLUSION: The real-time availability of functional mapping information in an interactive fashion can reduce surgical risk and minimize functional morbidity. Within the ever-expanding realm of functional mapping and image-guided neurosurgery, further progress and integration of these methods is critical for resection of lesions involving eloquent cortex
— id: 7036, year: 1996, vol: 39, page: 92, stat: Journal Article,

Primary central nervous system non-Hodgkin's lymphoma (PCNSL): does age and histology at presentation affect outcome?
Schaller C; Kelly PJ
1996 ;57(3):156-162, Zentralblatt fur Neurochirurgie
Primary Non-Hodgkin's lymphoma of the central nervous system (PCNSL) was diagnosed by computer-assisted stereotactic biopsy in 27 non-AIDS patients (22 men, 5 women; mean age, 50.6 years, median age 53 years). Among the various histologies, fourteen patients had diffuse large cell lymphoma (DLC), five had diffuse, small, non-cleaved lymphoma (DSNC) and five had diffuse mixed cell lymphoma (DMC). Immunohistochemical analysis revealed 6 B-cell and 3 T-cell types. Multiple lesions occurred in 11 patients. Most patients received radiation therapy and some received adjunctive and/or salvage chemotherapy. Several factors correlated with survival, median survival for the entire group was 356 days (0.975 years). However, Median survival was 1982 days (5.43 years) for the 8 patients who were less than 45 years old at diagnosis versus 283 days (0.77 years) for the 18 patients who were older (p = 0.03). One patient was lost for follow up. Four of the 5 patients who have survived for more than four years were less than 45 years of age; of these 2 had T-cell lymphoma. Only 3 of the 11 patients with multiple lesions died within the first year. A proportional hazards model was derived for the group and suggested that older age and uncleaved histology are associated with shorter survival. Treatment protocols should include stratification factors to allow comparison between groups with different characteristics and to account for age and/or histology dependent on differences in response
— id: 33781, year: 1996, vol: 57, page: 156, stat: Journal Article,

A novel computer-assisted volumetric stereotactic approach for resecting tumors of the posterior parahippocampal gyrus
Weiner HL; Kelly PJ
1996 Aug;85(2):272-277, Journal of neurosurgery
The authors report their experience using a novel surgical approach for resecting tumors located in the posterior parahippocampal gyrus. Prior attempts to resect epileptogenic foci in this location have been limited by a significant risk of injury to lateral temporal lobe cortical and vascular structures. To avoid these potential complications, the authors have used a lateral occipitosubtemporal, computer-assisted stereotactic volumetric approach to resect radiographically defined tumors in seven patients with intraaxial neoplasms of the posteromedial temporal lobe. This series included one female and six male patients, ranging in age from 15 to 67 years, who presented with seizures, visual field loss, or headache. Gross-total resection of three high-grade gliomas, two gangliogliomas, and one mixed glioma was accomplished with no permanent morbidity or operative mortality. The authors conclude that this approach is advantageous for resecting tumors in this location because, by avoiding unnecessary brain resection or retraction, it significantly reduces the risk of injury to lateral temporal lobe structures, helps maintain precise spatial and anatomical orientation for the surgeon, and, like all computer-assisted volumetric approaches, delineates the margin between the tumor and surrounding neural tissue
— id: 8017, year: 1996, vol: 85, page: 272, stat: Journal Article,

Contrast-enhancing progressive multifocal leukoencephalopathy: radiological and pathological correlations: case report
Woo HH; Rezai AR; Knopp EA; Weiner HL; Miller DC; Kelly PJ
1996 Nov;39(5):1031-1034, Neurosurgery
OBJECTIVE AND IMPORTANCE: Progressive multifocal leukoencephalopathy (PML), a demyelinating disease caused by the JC papovavirus, is an opportunistic infection afflicting patients with impaired cellular immunity. Although initially described in patients with hematological malignancies, PML has become associated with several other immunocompromised states, particularly human immunodeficiency virus (HIV) infection. There are numerous central nervous system manifestations in patients with acquired immunodeficiency syndrome. A major characteristic that distinguishes PML from other more common lesions, such as toxoplasmosis or non-Hodgkin's lymphoma, is the lack of contrast enhancement. We describe a case of PML that exhibits contrast enhancement, and we conclude that the diagnosis of PML must be considered in patients with HIV who have contrast-enhancing lesions. CLINICAL PRESENTATION: A 40-year-old woman presented with progressive hemiparesis, blurred vision, and ataxia. Magnetic resonance imaging revealed a contrast-enhancing lesion involving the left middle cerebellar peduncle, causing mild compression of the fourth ventricle. INTERVENTION: The patient underwent a stereotactic serial biopsy with the presumptive diagnosis of moderate- to high-grade glioma. Histological examination of the biopsy specimen revealed early PML. Subsequently, a test for HIV was obtained and the results were positive. CONCLUSION: We have reported another atypical radiographic characteristic of PML associated with HIV. We conclude that PML lesions can enhance after the administration of gadolinium. Therefore, the diagnosis of PML must be entertained in patients whose test results were positive for HIV with contrast-enhancing lesions and that a stereotactic serial biopsy may be necessary to provide a definitive diagnosis
— id: 12504, year: 1996, vol: 39, page: 1031, stat: Journal Article,

Stereotactic ventrolateral thalamotomy: is ventriculography necessary?
Alterman RL; Kall BA; Cohen H; Kelly PJ
1995 Oct;37(4):717-721, Neurosurgery
In the computed tomography/magnetic resonance imaging (CT/MRI) era, the need for ventriculography to perform ventrolateral thalamotomy accurately has been debated. We retrospectively compared CT/MRI-derived coordinates for ventrolateral thalamotomy with the final lesion coordinates that were determined by ventriculography and microelectrode recording in 74 thalamotomies performed from 1984 to 1994. The median three-dimensional distance between the CT/MRI-derived loci and the ventriculography/microelectrode loci was 4.7 mm (range, 1.0-11.7 mm). The techniques correlated least along the Y axis (median, -0.3 mm; range, -8.2 to 8.0 mm). Correlation along the X axis was most consistent (median, 0.5 mm; range, -4.2 to 5.0 mm). Since 1990, the CT/MRI-derived coordinates have been generated by a multimodality correlative imaging technique (MCIT). A comparison of thalamotomies performed with and without the MCIT revealed a significant improvement in the correlation of CT/MRI- and ventriculography/microelectrode-derived coordinates when the MCIT was employed. The greatest improvement was noted along the Y axis where the median absolute difference was reduced from 4.0 to 1.8 mm (P = 0.0001). The result was a statistically significant reduction in the median three-dimensional distance from 5.6 to 3.7 mm (P = 0.0007). The authors conclude that thalamotomies can be safely and effectively performed without ventriculography when the MCIT is employed and supported by neurophysiological monitoring
— id: 6801, year: 1995, vol: 37, page: 717, stat: Journal Article,

Pilocytic astrocytomas: well-demarcated magnetic resonance appearance despite frequent infiltration histologically
Coakley KJ; Huston J 3rd; Scheithauer BW; Forbes G; Kelly PJ
1995 Aug;70(8):747-751, Mayo Clinic proceedings
OBJECTIVE: To determine the magnetic resonance imaging (MRI) characteristics of pilocytic astrocytomas and to correlate them with the histopathologic findings. MATERIAL AND METHODS: MRI examinations and histopathologic findings in 56 patients with pilocytic astrocytomas were retrospectively reviewed. In 38 patients, findings on MRI were compared with those on computed tomography. RESULTS: The tumors occurred at all levels of the central nervous system, including the spinal cord. The intracranial tumors were periventricular (73%) or periaqueductal (9%). All tumors were typical pilocytic astrocytomas and were grade 1 on the basis of the World Health Organization classification. At operation, they were often circumscribed and cystic. Radiologically, the tumors were well demarcated (96%), had benign morphologic features, and almost always showed enhancement (94%). CONCLUSION: MRI of pilocytic astrocytomas typically demonstrated a relatively large, sharply demarcated periventricular mass with pronounced contrast enhancement but minimal or no associated edema. Often, the tumors were cystic on MRI. Despite the well-demarcated appearance grossly and on MRI, pathologic review showed that many of these tumors (64%) infiltrated the surrounding parenchyma, particularly the white matter
— id: 33677, year: 1995, vol: 70, page: 747, stat: Journal Article,

Radiation necrosis or glioma recurrence: is computer-assisted stereotactic biopsy useful?
Forsyth PA; Kelly PJ; Cascino TL; Scheithauer BW; Shaw EG; Dinapoli RP; Atkinson EJ
1995 Mar;82(3):436-444, Journal of neurosurgery
Fifty-one patients with supratentorial glioma treated with external beam radiotherapy (median dose 59.5 Gy) who then demonstrated clinical or radiographic evidence of disease progression underwent stereotactic biopsy to differentiate tumor recurrence from radiation necrosis. The original tumor histological type was diffuse or fibrillary astrocytoma in 21 patients (41%), oligodendroglioma in 13 (26%), and oligoastrocytoma in 17 (33%); 40 tumors (78%) were low-grade (Kernohan Grade 1 or 2). The median time to suspected disease progression was 28 months. Stereotactic biopsy showed tumor recurrence in 30 patients (59%), radiation necrosis in three (6%), and a mixture of both in 17 (33%); one patient (2%) had a parenchymal radiation-induced chondroblastic osteosarcoma. The tumor type at stereotactic biopsy was similar to the original tumor type and was astrocytoma in 24 patients (47%), oligodendroglioma in eight (16%), oligoastrocytoma in 16 (31%), unclassifiable in two (4%), and chondroblastic osteosarcoma in one patient (2%). At biopsy, however, only 19 tumors (37%) were low grade (Kernohan Grade 1 or 2). Subsequent surgery confirmed the stereotactic biopsy histological findings in eight patients. Follow-up examination showed 14 patients alive with a median survival of 1 year for the entire group. Median survival times after biopsy were 0.83 year for patients with tumor recurrence and 1.86 years for patients with both tumor recurrence and radionecrosis; these findings were significantly different (p = 0.008, log-rank test). No patient with radiation necrosis alone died. Other factors associated with reduced survival were a high proportion of residual tumor (p = 0.024), a low proportion of radionecrosis (p < 0.001), and a Kernohan Grade of 3 or 4 (p = 0.005). In conclusion, in patients with previously irradiated supratentorial gliomas in whom radionecrosis or tumor recurrence was clinically or radiographically suspected, results of stereotactic biopsy could be used to differentiate tumor recurrence, radiation necrosis, a mixture of both lesions, or radiation-induced neoplasm. In addition, biopsy results could predict survival rates
— id: 33637, year: 1995, vol: 82, page: 436, stat: Journal Article,

Pallidotomy in Parkinson's disease
Kelly PJ
1995 Jun;36(6):1154-1157, Neurosurgery
— id: 33780, year: 1995, vol: 36, page: 1154, stat: Journal Article,

Quantitative virtual reality enhances stereotactic neurosurgery
Kelly PJ
1995 Nov;80(11):13-20, Bulletin of the American College of Surgeons
— id: 12029, year: 1995, vol: 80, page: 13, stat: Journal Article,

State of the Art and Future Directions of Minimally Invasive Stereotactic Neurosurgery
Kelly PJ
1995 Jul;2(4):287-292, Cancer control
The use of endoscopic techniques in neurosurgery has been limited to this point. Unlike gynecologic, urologic, and general surgery, the majority of neurosurgery is not performed in a large gas- or fluid-filled cavity. Endoscopic techniques, therefore, usually have been used for limited procedures within the ventricular system. A minimally invasive technique for intra-axial surgery, which is dependent on precise, three-dimensional navigation within the intracranial space, is provided by computer-assisted volumetric stereotaxis. Over 1000 tumor resection procedures employ volumetric stereotaxis, and these procedures not only have less morbidity than conventional procedures with similar pathology in the same locations, but also are cost-effective. Experience with these procedures has opened up many possibilities for future development of minimally invasive techniques in neurosurgery
— id: 11641, year: 1995, vol: 2, page: 287, stat: Journal Article,

Surgical issues in the management of supratentorial low-grade gliomas
Kelly PJ
1995 ;42:399-436, Clinical neurosurgery
— id: 12817, year: 1995, vol: 42, page: 399, stat: Journal Article,

Computer-assisted volumetric stereotactic neurosurgery: present methodology and future directions
Kelly, P J
1995 ;IV:387-392, Surgical technology international
Classic craniotomy for biopsy or resection of intra-axial brain tumors usually employed large skin flaps and craniotomy openings. These were necessary so that surgeons could be certain that a subcortical tumor could be localized and that the extent of the lesion lay somewhere beneath and within the limits of the craniotomy. Localization methods for classic resection methods were qualitative and imprecise
— id: 127239, year: 1995, vol: IV, page: 387, stat: Journal Article,

Introduction of magnetoencephalography to stereotactic techniques
Rezai AR; Hund M; Kronberg E; Deletis V; Zonenshayn M; Cappell J; Ribary U; Llinas R; Kelly PJ
1995 ;65(1-4):37-41, Stereotactic & functional neurosurgery
Magnetoencephalography (MEG), a noninvasive functional brain mapping technique, was used for preoperative localization of the sensorimotor cortex in patients harboring lesions involving these eloquent regions. Prior to surgery, MEG source locations were transferred onto high-resolution MRI pictures which were then used for preoperative evaluation, risk analysis, and planning. We have developed a process to transform the MEG-derived sensorimotor localization coordinates into the COMPASS stereotactic coordinate system. Thus the MEG-derived functional information is incorporated into the stereotactic database, enabling the simultaneous visualization of functional and anatomical data. This information can be used for the selection of cases and in planning safe approaches for computer-assisted volumetric resections. The integration of MEG and stereotactic neurosurgery also allows a more precise comparison between MEG and intraoperative direct electrocorticographic mapping (ECoG). Seven patients were studied with good correlation between MEG and intraoperative mapping. In 4, the correlation was only based on gross visual comparison between intraoperative identification of the gyrus pattern and MEG photographs. The availability of the MEG coordinates in the stereotactic system, however, allows a more precise correlation between MEG and ECoG. In all 3 patients studied in this manner, the MEG coordinates (pinpointed to a precise cortical representation of a few millimeters) overlapped with ECoG results. In summary, we compared functional MEG data to intraoperative ECoG and conclude that the introduction of MEG into stereotactic neurosurgery can provide precise functional and anatomic information for image-guided surgical planning and resection
— id: 9893, year: 1995, vol: 65, page: 37, stat: Journal Article,

Primary intracerebral malignant lymphoma: a clinicopathological study of 89 patients
Tomlinson FH; Kurtin PJ; Suman VJ; Scheithauer BW; O'Fallon JR; Kelly PJ; Jack CR Jr; O'Neill BP
1995 Apr;82(4):558-566, Journal of neurosurgery
The authors report on a clinicopathological study of 89 surgical patients with histologically proven primary parenchymal brain lymphoma, all diagnosed between January 1975 and December 1990. The cohort included 60 men and 29 women whose median age at diagnosis was 60 years (range 14 to 84 years). The duration of symptoms was less than 8 weeks in 48% of the patients. Symptom groups included focal neurological deficit (73%), neuropsychiatric symptoms (28%), seizures (9%), and increased intracranial pressure (3%). A total of 132 tumors were seen in 89 patients: the most common sites were frontal (32 patients), temporoparietal (31 patients), and basal ganglia (17 patients); multiple lesions were reported in 23 patients. No patient had antecedent of human immunodeficiency virus positivity or acquired immunodeficiency syndrome. A family history of cancer was present in 33% of the patients, three-quarters of whom were first-degree relatives. Histological subtypes (National Cancer Institute Working Formulation) included 64 large cell (72%) and 13 immunoblastic (15%) tumors. Phenotype was determined in 66 patients: 63 were B-cell type and three were T-cell type. Surgical resection was performed in 47% of the cases, with the remainder undergoing biopsy only. All but six patients received radiation therapy. Thirty-one patients received chemotherapy, whereas 46 patients did not; data on the remaining 12 patients were unavailable. The end point of the study was death from any cause. At the time of last contact, 69 of the patients (78%) had died; the median survival time for this study group was 20.9 months. On univariate analysis, prognostic factors significantly associated with survival included age at diagnosis, family history of cancer, and focal neurological deficit. Multivariate analysis revealed four unfavorable prognostic factors: age greater than or equal to 60 years, history of cancer in first-degree relatives, focal deficit, and ependymal contact. After adjustment for these variables, clinical syndrome, size and number of lesions, extent of surgery, histological cell type, radiation dose, and use of chemotherapy were not significantly associated with survival
— id: 33638, year: 1995, vol: 82, page: 558, stat: Journal Article,

Low-grade glial neoplasms and intractable partial epilepsy: efficacy of surgical treatment
Britton JW; Cascino GD; Sharbrough FW; Kelly PJ
1994 Nov-Dec;35(6):1130-1135, Epilepsia
We performed a retrospective study of 51 consecutive patients who underwent operation for intractable partial epilepsy related to low-grade intracerebral neoplasms between 1984 and 1990. All patients had medically refractory partial seizures and a mass lesion identified on neuroimaging studies. Lesionectomy was performed on 17 patients, and 34 had lesion resection and corticectomy. Mean postoperative follow-up was 4.4 years (range 2-8 years). Sixty-six percent of patients were seizure-free, and 88% experienced a significant reduction in seizure frequency. In 16 patients (31%), antiepileptic drugs (AEDs) were successfully discontinued. Twenty-five of 31 (81%) eligible patients obtained a driver's license after successful operation. Patients with complete tumor resection and no interictal epileptiform activity on postoperative EEG studies had the best operative outcome. Epilepsy surgery can result in long-term improvement in seizure control and quality of life (QOL) in selected patients with intractable tumor-related epilepsy. Our results should be useful to clinicians considering treatment options for patients with intractable seizures related to low-grade intracerebral neoplasms
— id: 33642, year: 1994, vol: 35, page: 1130, stat: Journal Article,

Extratemporal cortical resections and lesionectomies for partial epilepsy: complications of surgical treatment
Cascino GD; Sharbrough FW; Trenerry MR; Marsh WR; Kelly PJ; So E
1994 Sep-Oct;35(5):1085-1090, Epilepsia
Fifty patients with medically refractory extratemporal seizures underwent epilepsy surgery at our institution between 1988 and 1992. Twenty-nine patients (group I) had an extratemporal (mainly frontal lobe) corticectomy, and 21 patients (group II) had an epileptogenic lesion extirpated without resection of the epileptic brain tissue. Comprehensive neurologic evaluation was performed preoperatively, soon after operation, and approximately 3 months postoperatively to assess operative outcome. Magnetic resonance imaging (MRI) in group I patients usually showed no abnormality or a large destructive lesion. Neuroimaging showed a foreign tissue lesion in most group II patients. Thirteen of the 29 patients who underwent corticectomy had at least one adverse event (AE) potentially related to operation at the time of initial assessment. Four of the 13 patients required a surgical procedure to treat the operative complication, but only 1 of the 13 patients had a persistent neurologic deficit at follow-up examination. Three of the 21 patients who received lesionectomy had acute and persistent neurologic morbidity. Patients undergoing cortical resection remained intubated longer postoperatively (p < 0.005), and required longer hospitalization after operation (p < 0.001) and in the intensive care unit (p < 0.001) as compared with the lesionectomy group. Results of this study may prove useful in counseling patients regarding neurologic outcome after extratemporal surgery
— id: 33643, year: 1994, vol: 35, page: 1085, stat: Journal Article,

Changes in proliferating cell nuclear antigen expression in glioblastoma multiforme cells along a stereotactic biopsy trajectory
Dalrymple SJ; Parisi JE; Roche PC; Ziesmer SC; Scheithauer BW; Kelly PJ
1994 Dec;35(6):1036-1044, Neurosurgery
Proliferating cell nuclear antigen, an auxiliary protein of deoxyribonucleic acid polymerase-delta, has been shown to be a reliable marker of nuclear deoxyribonucleic acid synthetic activity. We applied a monoclonal antibody to proliferating cell nuclear antigen to a series of serial stereotactic biopsies from patients with glioblastoma multiforme and found the proliferative activity to vary relative to biopsy location within or surrounding the solid tissue component of the tumor. Twenty-seven trajectories in 26 patients were analyzed, each consisting of two to five sequential 10 x 1.5 mm core biopsies (mean = 3). The proliferative index (PI) was greatest in those cells located at the solid tumor-infiltrated parenchyma interface. PI values were significantly lower in those biopsy cores located proximal (within infiltrated parenchyma) and distal (within solid tumor tissue) to the solid tumor-infiltrated parenchyma interface (median PI values, proximal to distal: 0.38, 0.66, 5.45 solid tumor-infiltrated parenchyma interface], 0.39, 0.09%). The mean PI values were significantly lower in neoplastic cells samples from regions of peripheral hypodensity on computed tomographic scans compared with those sampled from contrast-enhancing regions (0.9 and 3.91%, respectively). There was no significant difference in the mean PI values of neoplastic cells sampled from regions of contrast enhancement or central hypodensity (3.91 and 4.31%, respectively)
— id: 33655, year: 1994, vol: 35, page: 1036, stat: Journal Article,

Symptomatic glial cysts of the pineal gland
Fain JS; Tomlinson FH; Scheithauer BW; Parisi JE; Fletcher GP; Kelly PJ; Miller GM
1994 Mar;80(3):454-460, Journal of neurosurgery
Small asymptomatic cysts of the pineal gland represent a common incidental finding in adults undergoing computerized tomography or magnetic resonance (MR) imaging or at postmortem examination. In contrast, large symptomatic pineal cysts are rare, being limited to individual case reports or small series. The authors have reviewed 24 cases of large pineal cysts. The mean patient age at presentation was 28.7 years (range 15 to 46 years); 18 were female and six male. Presenting features in 20 symptomatic cases included: headache in 19; nausea and/or vomiting in seven; papilledema in five; visual disturbances in five (diplopia in three, 'blurred vision' in two, and unilateral partial oculomotor nerve palsy in one); Parinaud's syndrome in two; hemiparesis in one; hemisensory aberration in one; and seizures in one. Four lesions were discovered incidentally. Magnetic resonance imaging typically demonstrated a 0.8- to 3.0-cm diameter mass (mean 1.7 cm) with homogeneous decreased signal intensity on T1-weighted images, increased signal intensity on T2-weighted images, and a distinct margin. Hydrocephalus was present in eight cases. The cysts were surgically excised via an infratentorial/supracerebellar approach (23 cases) or stereotactically biopsied (one case). Histological examination revealed a cyst wall 0.5 to 2.0 mm thick comprised of three layers: an outer fibrous layer, a middle layer of pineal parenchymal cells with variable calcification, and an inner layer of hypocellular glial tissue often exhibiting Rosenthal fibers and/or granular bodies. Evidence of prior hemorrhage, mild astrocytic degenerative atypia, and disorganization of pineal parenchyma were often present. Postoperative follow-up review in all 24 cases (range 3 months to 10 years) revealed no complications in 21, mild ocular movement deficit in one, gradually resolving Parinaud's syndrome in one, and radiographic evidence of a postoperative venous infarct of the superior cerebellum with ataxia of 1 week's duration in one. Of the patients referred for study, the cysts were most often initially misdiagnosed as a pineocytoma in eight and a pilocytic astrocytoma in three. Only two patients were correctly diagnosed as having pineal cysts. This stresses the importance of recognizing the histopathological spectrum of pineal cysts, as well as correlation with radiographic findings, if a correct diagnosis is to be attained
— id: 33639, year: 1994, vol: 80, page: 454, stat: Journal Article,

A stereotactic magnetic field digitizer
Goerss SJ; Kelly PJ; Kall B; Stiving S
1994 ;63(1-4):89-92, Stereotactic & functional neurosurgery
A three-dimensional magnetic field digitizer has been interfaced the COMPASS Stereotactic System to act as a measuring device aiding in computer-assisted volumetric procedures. Reference points on the stereotactic headholder are used to create a transformation matrix to convert the digitizer coordinates to stereotactic coordinates, allowing the location of the stylus to be displayed on CT and reconstructed tumor volume images to maintain the surgeon's orientation. This technology is an adjunct to and employs treatment planning software of the system to calculate a target and determine a safe trajectory to a lesion. Environmental effects of the magnetic field have been studied to determine overall accuracy and reliability of the system. A device was developed to map the magnetic field in efforts to compensate for environmental effects. The device has been utilized on five procedures. We have found it to be a useful tool in aiding the surgeon in locating the surgical field preoperatively and maintaining orientation intraoperatively
— id: 33699, year: 1994, vol: 63, page: 89, stat: Journal Article,

Sensory motor cortex: correlation of presurgical mapping with functional MR imaging and invasive cortical mapping
Jack CR Jr; Thompson RM; Butts RK; Sharbrough FW; Kelly PJ; Hanson DP; Riederer SJ; Ehman RL; Hangiandreou NJ; Cascino GD
1994 Jan;190(1):85-92, Radiology
PURPOSE: To describe a clinically useful application of functional magnetic resonance (MR) imaging--presurgical mapping of the sensory motor cortex--and to validate the results with established physiologic techniques. MATERIALS AND METHODS: Functional MR mapping of the sensory motor cortex was performed in two women, aged 24 and 38 years. Both had intractable, simple partial motor seizures due to tumors located in or near the sensory motor cortex. They subsequently underwent invasive cortical mapping--direct cortical stimulation and/or sensory-evoked-potential recording--to localize the affected sensory motor area prior to tumor resection. RESULTS: In both patients, the functional MR study demonstrated task activation of the sensory motor cortex. In both cases, results of cortical functional mapping with invasive techniques matched those obtained with functional MR imaging. CONCLUSION: Presurgical mapping of the sensory motor cortex is a potentially useful clinical application of functional MR imaging
— id: 33644, year: 1994, vol: 190, page: 85, stat: Journal Article,

Three-dimensional display in the evaluation and performance of neurosurgery without a stereotactic frame: more than a pretty picture?
Kall BA; Goerss SJ; Kelly PJ; Stiving SO
1994 ;63(1-4):69-75, Stereotactic & functional neurosurgery
Display of three-dimensionally rendered images derived from radiological data sets is often suggested to be useful for surgical and radiation treatment planning in neurosurgery. Nevertheless, physicians will often note (off the record) that these rendered images are 'just a pretty picture' and are not clinically useful. This paper will discuss our three-dimensional rendering and quantitative analysis software and its primary use in evaluating and utilizing frameless stereotactic methodologies. A variety of concepts and techniques will be discussed. Specifically, a computer graphic and statistical-based technique will be presented that enables timely and measurable image registration between radiological image space and the coordinate system of computer-driven surgical devices in the operating room. This technique may be utilized to maintain a surgeon's orientation and to quantitatively and graphically monitor the position of probes and instruments in the surgical field. Three-dimensional quantitative results of phantom testing will be presented. Correlation to and validation against stereotactic imaging calculations using the compass stereotactic system will also be discussed. These computer graphic/statistical-based techniques are applicable for evaluating the accuracy of any frameless stereotactic device including, but not limited to robotic arms, spark gap, LED and magnetic field digitizers
— id: 33700, year: 1994, vol: 63, page: 69, stat: Journal Article,

The limited value of cytoreductive surgery in elderly patients with malignant gliomas
Kelly PJ; Hunt C
1994 Jan;34(1):62-66, Neurosurgery
In this retrospective, consecutive series of 128 elderly patients (over 65 years of age) with histologically proven Grade 4 astrocytomas, 88 patients underwent stereotactic biopsy and 40 patients underwent stereotactic volumetric resection of the mass lesion defined by contrast enhancement on computed tomography. There were no significant differences in age (average age in the biopsy group, 71.6 yr; resection group, 70.15 yr) or Karnofsky Performance Scores (biopsy group, 84.33; resection group, 83.88) between the two groups. Four of the biopsy patients and one of the resection patients died within 30 days of surgery. The overall mean survival was 126 days; 108 days (15.4 wk) in the patients who had biopsies and 189 days (27 wk) in the patients who had resections. Radiation therapy was completed in 62 of the patients who had biopsies (mean survival, 118 d or 16.9 wk) and 34 of the patients undergoing resection (mean survival, 210 d or 30 wk) (log rank P = 0.0215; Smirnov P = 0.006). Although some prolongation of survival is noted after resection (more than after a biopsy) in selected patients over 65 years of age, that benefit is modest
— id: 33667, year: 1994, vol: 34, page: 62, stat: Journal Article,

Surgical treatment for epilepsy in cerebral tuberous sclerosis
Bebin EM; Kelly PJ; Gomez MR
1993 Jul-Aug;34(4):651-657, Epilepsia
Tuberous sclerosis (TS) is an autosomal dominant hamartiosis and hamartomatosis with variable expression that is commonly associated with medically intractable seizures. Patients with TS complex (TSC) frequently have multiple brain lesions that can give rise to seizure activity. We report 9 patients with TSC who underwent epilepsy surgery at the Mayo Clinic between 1986 and 1990. Surgical procedures performed included cortical resection (n = 2) and stereotaxic lesionectomy (n = 7). Neuropathologic diagnoses were cortical tubers (n = 7) and glioneural hamartomas (n = 2). Three of 9 patients had multifocal interictal scalp epileptiform EEG activity; however, ictal recordings identified the focus of seizure activity, which in all cases corresponded to a prominent neuroimaging abnormality. Our patients have been followed for 10-72 months (mean 35 months). Four patients are seizure-free with medication, 2 are seizure-free without medication, 2 had > 80% reduction in seizure frequency, and 1 experienced only an initial temporary reduction in seizure frequency. Postoperative EEG recordings showed absence of epileptiform abnormalities in the 5 patients who are seizure-free; the other 4 patients continue to have multifocal abnormalities. These data suggest that epilepsy surgery may be beneficial in selected patients with TSC despite multifocal EEG and neuroimaging abnormalities
— id: 33671, year: 1993, vol: 34, page: 651, stat: Journal Article,

Intracranial parenchymal schwannoma. A clinicopathological and neuroimaging study of nine cases
Casadei GP; Komori T; Scheithauer BW; Miller GM; Parisi JE; Kelly PJ
1993 Aug;79(2):217-222, Journal of neurosurgery
The clinical, radiological, and pathological features of nine cases of intracranial parenchymal schwannoma are described. The clinical course in four patients 23 years of age or younger mirrored the indolent nature of this neoplasm. Imaging studies included computerized tomography in eight patients and magnetic resonance imaging in three. The lesions were well demarcated with only mild surrounding edema. Five tumors were deep within the temporoparieto-occipital region, three were in the cerebellum, and one lay peripherally in the parietal lobe. Over two-thirds of the nine tumors were either cystic (five) or contained areas of cystic degeneration (two). One lesion was frankly hemorrhagic. A variety of imaging characteristics and contrast enhancement patterns were observed, including those of a cyst with a mural nodule and peripheral enhancement. Of the four solid neoplasms, two enhanced homogeneously while the other two demonstrated heterogeneous enhancement. Six tumors were resected totally. The follow-up period ranging from 2 months to 2 years has shown no recurrences. Microscopically, immunohistochemically, and ultrastructurally, the tumors were indistinguishable from peripheral schwannomas. A possible mechanism underlying the histogenesis of these rare lesions is discussed. The importance of recognizing this tumor is stressed, particularly in younger patients, given its benign nature, radiological resemblance to other tumors such as pilocytic astrocytoma, and favorable response to resection
— id: 33676, year: 1993, vol: 79, page: 217, stat: Journal Article,

Gelastic seizures and hypothalamic hamartomas: evaluation of patients undergoing chronic intracranial EEG monitoring and outcome of surgical treatment
Cascino GD; Andermann F; Berkovic SF; Kuzniecky RI; Sharbrough FW; Keene DL; Bladin PF; Kelly PJ; Olivier A; Feindel W
1993 Apr;43(4):747-750, Neurology
We retrospectively studied 12 consecutive patients with gelastic seizures and hypothalamic hamartomas who, because of intractable epilepsy, underwent chronic intracranial EEG monitoring or epilepsy surgery. All patients had medically refractory seizures that included laughter as an ictal behavior (gelastic seizures). The hypothalamic hamartomas were identified with neuroimaging studies (12 of 12) and by pathologic verification (four of 12). Associated clinical features included behavioral disorders (n = 5), developmental delay (n = 4), and precocious puberty (n = 2). Interictal extracranial EEG predominantly showed bi-hemispheric epileptiform changes suggesting a secondary generalized epileptic disorder. Intracranial EEG recordings, performed in eight patients, indicated the apparent focal onset of seizure activity (anterior temporal lobe [n = 7] and frontal lobe [n = 1]). None of the seven patients who underwent a focal cortical resection, however, experienced a significant reduction in seizure tendency. An anterior corpus callosotomy, performed in two patients with symptomatic generalized epilepsy, resulted in a worthwhile reduction in drop attacks. Results of this study may modify the surgical strategies in patients with gelastic seizures and hypothalamic hamartomas
— id: 33649, year: 1993, vol: 43, page: 747, stat: Journal Article,

Parietal lobe lesional epilepsy: electroclinical correlation and operative outcome
Cascino GD; Hulihan JF; Sharbrough FW; Kelly PJ
1993 May-Jun;34(3):522-527, Epilepsia
We retrospectively studied ictal behavior, extracranial EEG, and operative outcome in 10 consecutive patients with intractable partial epilepsy of presumed parietal lobe origin who received a lesionectomy, i.e., resection of the neuroimaging-identified abnormality, at the Mayo Clinic. Nine patients had a pathologically verified foreign-tissue lesion, e.g., tumor or vascular malformation, and 1 patient had gliosis. All patients with foreign-tissue lesions were rendered seizure-free. The patient with gliosis experienced a reduction in seizure tendency. There were no operative complications. The most common seizure type was a simple partial seizure with visual, motor, or sensory symptoms (n = 8). Complex partial seizures (n = 5) and secondarily generalized tonic-clonic seizures (GTC, n = 2) were also observed. The ictal behavior was often nonspecific although useful in identifying lateralization of the epileptogenic zone. Extracranial interictal and ictal EEG changes were unreliable markers of the parietal lobe origin of seizure activity. Lesionectomy without chronic intracranial monitoring or functional mapping may be an effective and safe alternative surgical procedure in patients with partial epilepsy related to parietal lobe lesions
— id: 33648, year: 1993, vol: 34, page: 522, stat: Journal Article,

Operative strategy in patients with MRI-identified dual pathology and temporal lobe epilepsy
Cascino GD; Jack CR Jr; Parisi JE; Sharbrough FW; Schreiber CP; Kelly PJ; Trenerry MR
1993 Feb;14(2):175-182, Epilepsy research
We performed a prospective study using preoperative magnetic resonance imaging to identify hippocampal formation atrophy in 15 consecutive patients with intractable partial epilepsy who had undergone a stereotactic resection of an extrahippocampal temporal lobe foreign-tissue lesion. A stereotactic lesionectomy was performed in all patients, i.e., only the imaging-defined lesion itself was resected. Hippocampal formation atrophy was identified in three of the 15 patients. Neuroimaging-detected hippocampal formation atrophy has been shown to be a reliable marker of moderate to severe mesial temporal sclerosis. All patients with hippocampal formation atrophy had an unfavorable operative outcome. Pathological examination of the hippocampus in one patient with neuroimaging-identified hippocampal formation atrophy who subsequently received an anterior temporal lobectomy revealed mesial temporal sclerosis. Nine of the 12 patients without hippocampal formation atrophy experienced a significant reduction in seizure tendency after lesionectomy. The surgically excised hippocampus in one patient without hippocampal formation atrophy who later underwent a temporal lobectomy showed no significant neuronal loss. Results of this study have modified the surgical approach taken at this institution in patients with temporal lobe lesional epilepsy. Patients with magnetic resonance imaging-defined dual pathology now undergo a temporal lobectomy which includes resection of the hippocampus and the foreign-tissue lesion
— id: 33650, year: 1993, vol: 14, page: 175, stat: Journal Article,

MRI assessments of hippocampal pathology in extratemporal lesional epilepsy
Cascino GD; Jack CR Jr; Sharbrough FW; Kelly PJ; Marsh WR
1993 Nov;43(11):2380-2382, Neurology
We performed a prospective study in 18 patients to determine the extent of MRI-identified hippocampal pathology in patients with intractable partial epilepsy of extratemporal origin. A mesial temporal signal-intensity alteration or hippocampal formation (HF) atrophy, or both, have been shown to be reliable markers of the temporal lobe of seizure origin in patients with mesial temporal sclerosis. All patients subsequently received surgical ablative therapy between 1988 and 1992. During shortterm follow-up, 14 of the 18 patients experienced a significant reduction in seizure tendency, and 12 patients were rendered seizure-free. Qualitative and quantitative (HF volumetry) assessments of HF pathology were performed retrospectively by a blinded investigator. No hippocampal imaging alteration was present in 17 patients. Left HF atrophy was confirmed in one patient with post-traumatic epilepsy who underwent a successful right frontal lobectomy. Morphometric MRI studies rarely identify hippocampal pathology in patients with extratemporal epilepsy
— id: 33645, year: 1993, vol: 43, page: 2380, stat: Journal Article,

Resection, biopsy, and survival in malignant glial neoplasms. A retrospective study of clinical parameters, therapy, and outcome
Devaux BC; O'Fallon JR; Kelly PJ
1993 May;78(5):767-775, Journal of neurosurgery
Between July, 1984, and October, 1988, 263 patients (163 male, 100 female), aged from 4 to 83 years (mean 52 years), with malignant brain gliomas underwent surgical procedures: stereotactic biopsy in 160 and resection in 103 patients. There were 170 grade IV astrocytomas, 17 grade IV mixed oligoastrocytomas, 44 grade III astrocytomas, 22 grade III mixed oligoastrocytomas, and 10 malignant oligodendrogliomas. Overall median survival time was 30.1 weeks for grade IV gliomas, 87.7 weeks for grade III gliomas, and 171.3 weeks for malignant oligodendrogliomas. Multivariate analysis in 218 newly diagnosed cases revealed that the variables most strongly correlated with survival time were: tumor grade, patient age, seizures as a first symptom, a Karnofsky Performance Scale score of less than 70%, tumor resection, and a radiation therapy dose greater than 50 Gy. The proportions of patients receiving tumor resection versus biopsy in each of these prognosis factor groups were similar. Since most of the 22 patients with midline and brain-stem tumors were treated with biopsy alone, these were excluded. Considering 196 newly diagnosed patients with cortical and subcortical tumors, grade IV glioma patients undergoing resection of the contrast-enhancing mass (as evidenced on computerized tomography and magnetic resonance imaging) and postoperative external beam radiation therapy lived longer than those undergoing biopsy only and radiation therapy (median survival time 50.6 weeks and 33.0 weeks, respectively; Smirnov test, p = 0.0380). However, survival in patients with resected grade III gliomas was no better than in those with biopsied grade III lesions (p = 0.746). The authors conclude that, in selected grade IV gliomas, resection of the contrast-enhancing mass followed by radiation therapy is associated with longer survival times than radiation therapy after biopsy alone
— id: 33693, year: 1993, vol: 78, page: 767, stat: Journal Article,

Astrocytomas of the cerebellum. A comparative clinicopathologic study of pilocytic and diffuse astrocytomas
Hayostek CJ; Shaw EG; Scheithauer B; O'Fallon JR; Weiland TL; Schomberg PJ; Kelly PJ; Hu TC
1993 Aug 1;72(3):856-869, Cancer
BACKGROUND. The majority of patients with astrocytomas of the cerebellum have an excellent prognosis; however, a small percentage of patients continue to do poorly. To clarify the clinical, pathologic, and treatment characteristics that determine prognosis and therapeutic recommendations, a large group of patients with astrocytic tumors of the cerebellum was reviewed and analyzed. METHODS. A clinicopathologic analysis was performed of all patients undergoing initial operation for astrocytomas in the cerebellum between 1960 and 1984. Of the 132 patients, 105 patients had pilocytic astrocytomas and 27 had diffuse astrocytomas. RESULTS. Multivariate analysis revealed that the division of pilocytic and diffuse histologic type was the most significant prognostic factor influencing survival. The 5-year, 10-year, and 20-year survival rates were 85%, 81%, and 79%, respectively, for patients with pilocytic astrocytomas and 7%, 7%, and 7%, respectively, for patients with diffuse astrocytomas (P < 0.001). Pilocytic astrocytomas occurred in a younger age group and were more commonly cystic and completely resected. CONCLUSIONS. Astrocytomas of the cerebellum can be divided into two principal groups, the pilocytic and the diffuse astrocytomas, each of which has distinct clinical, pathologic, and prognostic characteristics
— id: 33669, year: 1993, vol: 72, page: 856, stat: Journal Article,

Computed tomography and histologic limits in glial neoplasms: tumor types and selection for volumetric resection
Kelly PJ
1993 Jun;39(6):458-465, Surgical neurology
Selective and accurate resection of any computed tomography (CT) or magnetic resonance imaging (MRI) defined intracranial volume is possible by employing imaging-based computer-assisted volumetric stereotactic methods. Although the target volume can be any intracranial lesion, volumetric resection techniques were most frequently applied to the most commonly referred intraaxial lesions: glial neoplasms located in eloquent brain regions. Requirements for understanding of glial neoplasms as target volumes prompted investigations of the three-dimensional spatial configuration of these lesions, their histologic margins, and the accuracy with which these margins could be detected on CT and MRI. Stereotactic serial biopsy studies have shown that glial neoplasms frequently comprise two elements: tumor tissue and isolated tumor cells which infiltrate brain parenchyma. The tumor tissue component of high grade gliomas is most accurately defined by the volume which exhibits contrast enhancement. However, tumor tissue in low grade (nonpilocytic) gliomas is usually indistinguishable from infiltrated parenchyma on CT and MRI; both are hypodense on CT and do not usually exhibit contrast enhancement. Stereotactic serial biopsy is the only reliable method by which CT hypodense tumor tissue can be differentiated from infiltrated parenchyma in low grade (nonpilocytic) astrocytomas, oligodendrogliomas, and mixed gliomas. Stereotactic volumetric resection of infiltrated parenchyma defined by CT/MRI is advisable only in nonessential brain regions. In eloquent brain areas, stereotactic resection is appropriate for the glial tumor tissue component of high grade glial neoplasms, pilocytic astrocytomas, and low grade CT hypodense gliomas in which a stereotactic serial biopsy procedure has confirmed tumor tissue only
— id: 33779, year: 1993, vol: 39, page: 458, stat: Journal Article,

Thoralf M. Sundt, Jr., M.D., 1930-1992
Kelly PJ
1993 Jan;78(1):1-4, Journal of neurosurgery
— id: 33778, year: 1993, vol: 78, page: 1, stat: Journal Article,

Resection of intraventricular tumors via a computer-assisted volumetric stereotactic approach
Morita A; Kelly PJ
1993 Jun;32(6):920-926, Neurosurgery
Intraventricular tumors present a major challenge for neurosurgeons because of their depth and the important structures around them. Between 1984 and 1991, we performed 60 computer-assisted volumetric stereotactic resection procedures in 58 patients with intraventricular tumors (30 patients with third ventricular tumors and 28 patients with lateral ventricular tumors). The pathological findings of the tumors were as follows: colloid cyst in 27, giant cell astrocytoma in 5, central neurocytoma in 4, pilocytic astrocytoma in 4, meningioma in 3, subependymoma in 3, metastatic tumor in 3, oligodendroglioma in 2, ependymoma in 2, and miscellaneous tumors in 5 patients. Most presenting symptoms were nonlocalized--headache or cognitive dysfunction. All third ventricular tumors were approached via a frontal trajectory, and lateral ventricular tumors were approached according to the site and shape of the lesion. Total resection was achieved in 55 procedures. Overall outcome was excellent in 45 cases, good (some deficit but independent) in 5, and poor (dependent) in 3 (memory impairment, 2 patients; visual field cut, 1 patient). Two patients (3.4%) died postoperatively (one had a postoperative thalamic hemorrhage and pulmonary embolus; one had a subdural hygroma). In follow-up, three patients died from the extension of a malignant tumor or from primary cancer. Permanent morbidity was seen in three cases (5%). The authors believe computer-assisted volumetric stereotaxis is useful in removing intraventricular tumors. This technique allows us to find a safe trajectory and to locate and separate the tumor margin from the surrounding vital structures
— id: 33692, year: 1993, vol: 32, page: 920, stat: Journal Article,

Stereotactic procedures for lesions of the pineal region
Popovic EA; Kelly PJ
1993 Oct;68(10):965-970, Mayo Clinic proceedings
During the 7-year period between June 1985 and May 1992, 34 patients with pineal lesions underwent 66 stereotactic procedures (37 biopsies, 19 third ventriculostomies, 6 cyst aspirations, 3 instillations of 32P into cysts, and 1 insertion of an Ommaya reservoir into a cyst) at the Mayo Clinic. Nine patients subsequently also underwent 10 open resections of lesions of the pineal region. In the 34 study patients, the pathologic entities were 9 gliomas (5 astrocytomas, 2 ependymomas, and 2 oligodendrogliomas), 9 germ cell tumors (7 germinomas, 1 entodermal sinus tumor, and 1 malignant teratoma), 8 pineal parenchymal tumors (3 pinealomas, 3 pinealoblastomas, 1 mixed pinealoma-pinealoblastoma, and 1 intermediate differentiation pineal tumor), 4 other malignant tumors (2 undifferentiated carcinomas, 1 malignant melanoma, and 1 non-Hodgkin's lymphoma), 2 meningiomas, and 2 nonneoplastic lesions (1 glial cyst and 1 inflammatory lesion). No mortality or permanent morbidity was associated with the 66 stereotactic procedures; 2 patients had temporary complications--1 neurologic (transient diplopia) and 1 nonneurologic (pulmonary embolism). Diagnostic tissue was obtained in 33 of the 34 patients. An algorithm for the diagnosis and management of patients with lesions of the pineal region is presented. We conclude that stereotactic biopsy of pineal lesions can be performed safely, has a high diagnostic yield, and facilitates rational planning of treatment
— id: 33670, year: 1993, vol: 68, page: 965, stat: Journal Article,

Oligodendrocyte injury is an early event in lesions of multiple sclerosis
Rodriguez M; Scheithauer BW; Forbes G; Kelly PJ
1993 Jul;68(7):627-636, Mayo Clinic proceedings
The ultrastructural features of 11 stereotaxic brain biopsy specimens that demonstrated inflammatory primary demyelination consistent with acute multiple sclerosis were examined. Uniform widening of inner myelin lamellae (biphasic myelinopathy) and degeneration of inner glial loops ('dying-back' oligodendrogliopathy) were early pathologic abnormalities that antedated complete destruction of myelin sheaths. Perivascular inflammatory cells (lymphocytes, macrophages, and occasional plasma cells) were in intimate contact with degenerating myelin sheaths. The response of astrocytes was prominent, even in areas of minimal demyelination. Oligodendrocytes were morphologically preserved in early lesions but proliferated at the periphery of active lesions. Thinly myelinated axons indicative of central nervous system-type remyelination by oligodendrocytes were observed primarily at the edge of plaques. Disturbances of the myelinating function of oligodendrocytes--unaccompanied by death of these cells--may be among the earliest pathologic features in multiple sclerosis
— id: 33678, year: 1993, vol: 68, page: 627, stat: Journal Article,

Pineal parenchymal tumors. Clinical, pathologic, and therapeutic aspects
Schild SE; Scheithauer BW; Schomberg PJ; Hook CC; Kelly PJ; Frick L; Robinow JS; Buskirk SJ
1993 Aug 1;72(3):870-880, Cancer
BACKGROUND. Pineal parenchymal tumors are rare; therefore, only limited clinical data regarding their behavior is available. This study was performed to provide further information regarding the pathologic features, clinical behavior, and response to therapy of these tumors. METHODS. This study includes data concerning 30 patients (15 male and 15 female patients) with pineal parenchymal tumors (PPT) diagnosed between 1939 and 1991. Based on gross and microscopic features, tumors were divided into four groups: pineocytomas (9); PPT with intermediate differentiation (4); mixed PPT exhibiting elements of both pineocytoma and pineoblastoma (2); and pineoblastomas (15). At the time of diagnosis, four patients had evidence of spinal seeding (two with pineoblastoma, two with PPT with intermediate differentiation). Twenty-two patients received radiation therapy (RT): 6 were treated to local fields, 7 to the whole brain, and 9 to the craniospinal axis. RESULTS. For patients who received RT and had a minimum follow-up of 6 months, local failure occurred in one of four patients with pineocytomas, zero of four patients with PPT with intermediate differentiation, one of two with mixed PPT, and four of nine (44%) with pineoblastomas. In patients receiving > or = 50 Gy to the primary tumor, 0 of 12 had local failure compared with 6 of 7 (86%) patients receiving lesser doses. Leptomeningeal failure occurred in zero of four patients with pineocytomas, zero of four patients with PPT with intermediate differentiation, one of two with mixed PPT, and four of nine with pineoblastomas. All leptomeningeal failures occurred in patients with persistent primary tumor. Of the patients with seeding tumors (PPT other than pineocytomas) one of seven (14%) developed leptomeningeal failure when treated with craniospinal irradiation, compared with four of eight (50%) treated to lesser volumes. The projected 1-year, 3-year, and 5-year survival rates of patients with pineocytomas were 100%, 100%, and 67%, and were 88%, 78%, and 58% for those with the other forms of PPT, respectively. CONCLUSIONS. RT recommendations are described in detail and include the use of doses of > or = 50 Gy to areas of gross disease and the administration of craniospinal irradiation in patients with tumors prone to seeding. Surgical, chemotherapeutic, and pathologic considerations are discussed
— id: 33668, year: 1993, vol: 72, page: 870, stat: Journal Article,

MRI hippocampal volumes and memory function before and after temporal lobectomy
Trenerry MR; Jack CR Jr; Ivnik RJ; Sharbrough FW; Cascino GD; Hirschorn KA; Marsh WR; Kelly PJ; Meyer FB
1993 Sep;43(9):1800-1805, Neurology
We investigated the relationship between preoperative MRI hippocampal volumes and clinical neuropsychological memory test data obtained before and after temporal lobectomy and amygdalohippocampectomy for intractable epilepsy in 44 left (LTL) and 36 right (RTL) temporal lobectomy patients. In LTL patients, the difference (right minus left hippocampal volume) between hippocampal volumes (DHF) was significantly (p < 0.001) correlated (r = 0.61) with postoperative verbal memory change as measured by a delayed memory percent retention score from the Wechsler Memory Scale-Revised, Logical Memory subtest. DHF was also positively associated with postoperative memory for abstract geometric designs in LTL patients (r = 0.49, p < 0.005). Resection of a relatively nonatrophic left hippocampus was associated with poorer verbal and visual memory outcome. In RTL patients, larger right adjusted (for total intracranial volume) hippocampal volume was associated with decline in visual-spatial learning, but not memory, following surgery. MRI hippocampal volume data appear to provide meaningful information in evaluating the risk for memory impairment following temporal lobectomy
— id: 33646, year: 1993, vol: 43, page: 1800, stat: Journal Article,

Quantitative MRI hippocampal volumes: association with onset and duration of epilepsy, and febrile convulsions in temporal lobectomy patients
Trenerry MR; Jack CR Jr; Sharbrough FW; Cascino GD; Hirschorn KA; Marsh WR; Kelly PJ; Meyer FB
1993 Jul;15(3):247-252, Epilepsy research
The relationships between preoperatively acquired MRI-based hippocampal volumes (HV), seizure disorder onset and duration, and early childhood febrile convulsions were investigated retrospectively with data from 72 left and 56 right temporal lobectomy patients. Patients with lesional pathology and heterotopic abnormalities were excluded. Age at development of spontaneous seizures unprovoked by an acute illness defined age of seizure disorder onset. Age of onset was subtracted from age at neurosurgery to determine duration. MRI variables included in this study were the right and left HV divided by total intracranial volume (RAHV, LAHV), and the right-left hippocampal difference (DHF). Partial correlations were used to better isolate relationships with onset of recurrent seizures corrected for age at surgery, and age at neurosurgery corrected for age of recurrent seizure onset. Partial correlations between age at neurosurgery and volume were not significant in either group. LAHV (r = 0.42, P < 0.0003) and DHF (r = -0.49, P < 0.0001) were correlated with age of onset in the left lobectomy group. Correlations in the right lobectomy group were not significant. The presence of a febrile convulsion was associated with smaller LAHV (F(1,70) = 10.54, P < 0.002) and larger DHF (F(1,70) = 11.36, P < 0.002) in left temporal lobectomy patients. The presence of a febrile convulsion in the right temporal group was associated with a slightly smaller DHF (F(1,56) = 5.90, P < 0.02), and slightly smaller RAHV (F(1,56) = 4.49, P < 0.04). These data suggest that hippocampal atrophy remains stable over the duration of temporal lobe onset seizure disorders, and is associated with early onset of recurrent seizures in left temporal patients.(ABSTRACT TRUNCATED AT 250 WORDS)
— id: 33647, year: 1993, vol: 15, page: 247, stat: Journal Article,

Pioneers of stereotactic neurosurgery
al-Rodhan NR; Kelly PJ
1992 ;58(1-4):60-66, Stereotactic & functional neurosurgery
The beginnings of stereotactic and functional neurosurgery can be traced as far back as 1873 when Dittmar reported the use of a guiding device for the placement of probes into the medulla oblongata in animals. Further pioneering work was done by Zernov and Altukhov in Russia (1889), Clarke and Horsley in England (1908), and Spiegel and Wycis in the United States (1947), as well as others. After a promising initiation, interest in stereotactic neurosurgery waned after the introduction of L-dopa in the 1960s. Later, the introduction and incorporation of new imaging technology into stereotactic techniques signaled the rebirth of stereotactic and functional neurosurgery as a versatile and exciting subspecialty not only in the resection of previously unresectable lesions but also in the functional restoration of central nervous system function. This brief paper will focus on the personalities that have pioneered stereotactic neurosurgery over the past century
— id: 33673, year: 1992, vol: 58, page: 60, stat: Journal Article,

Surgical outcome in computer-assisted stereotactic resection of intra-axial cerebral lesions for partial epilepsy
al-Rodhan NR; Kelly PJ; Cascino GD; Sharbrough FW
1992 ;58(1-4):172-177, Stereotactic & functional neurosurgery
A retrospective analysis was performed in 30 patients who underwent computer-assisted stereotactic resection of intra-axial mass lesions with intractable partial epilepsy. Mean follow-up was 4.1 years (2-5.5), mean age 21 years (3-45) and mean duration of seizures 8.4 years (1-26). Pathology consisted of vascular malformations in 11, glial neoplasms in 11, cortical dysplasia in 4 and gliosis in 3, and no diagnostic abnormality was found in 2 patients. The location of the lesions in some cases may have precluded a standard craniotomy and cortical resection, e.g. precentral gyrus (5), post-central gyrus (5) and deep-seated left posterior temporal region (4). Operative morbidity involved 3 patients who developed motor or language deficits. Four patients were lost to follow-up. Thirteen patients out of 26 (50%) were class I, 3 (12%) were class II, 4 (15%) were class III and 6 (23%) were class IV. These findings suggest that stereotactic lesion resection in selected cases (e.g. where lesions are located in eloquent brain regions) can be useful in providing a histological diagnosis of the epileptogenic foci and result in a favorable reduction in seizure activity without the need for a standard cortical resection
— id: 33653, year: 1992, vol: 58, page: 172, stat: Journal Article,

Comparison of the neurochemistry of the endogenous opioid systems in two brainstem pain-processing centers
al-Rodhan NR; Yaksh TL; Kelly PJ
1992 ;59(1-4):15-19, Stereotactic & functional neurosurgery
SCH-32615 is a new enkephalinase inhibitor whose analgesic effects were examined following its stereotactic microinjection into the periaqueductal gray (PAG) and the ventromedial medulla (VMM) regions of the brainstem of the rat. SCH-32615 produced a strong, dose-dependent, naloxone-reversible analgesia to thermal noxious stimuli as measured by the hot plate test (HP; supraspinal analgesia) and the tail flick test (TF; spinal analgesia). The peak analgesic effect was seen within 10 min and remained for 45-60 min. ED50 were for PAG, HP = 10.7 micrograms and TF = 17.3 micrograms, and for VMM, HP = 5.7 micrograms and TF = 7.2 micrograms. Using the irreversible mu receptor antagonist, beta-funaltrexamine, it was found that the endogenous enkephalins in the PAG produce their analgesic effects by acting at only one receptor subtype (the mu receptor) while in the VMM both mu and delta opioid receptors are involved (not through the delta alone as previously believed)
— id: 33675, year: 1992, vol: 59, page: 15, stat: Journal Article,

Volumetric stereotactic resection of superficial and deep seated intraaxial brain lesions
Camacho A; Kelly PJ
1992 ;54(4):83-88, Acta neurochirurgica. Supplementum
From 1984 to 1989 a total of 374 computer-assisted stereotactic resections based on computed tomography or magnetic resonance imaging were performed on 337 supratentorial and 37 infratentorial brain lesions. Computer-assisted stereotactic volumetric resection allows a more aggressive extirpation of tumours with less damaging of the adjacent brain tissue. This procedure is of most benefit in deep seated circumscribed lesions and of less benefit in infiltrating tumours such as high grade gliomas and in fibrillary astrocytomas located in essential brain areas
— id: 33694, year: 1992, vol: 54, page: 83, stat: Journal Article,

MRI in the presurgical evaluation of patients with frontal lobe epilepsy and children with temporal lobe epilepsy: pathologic correlation and prognostic importance
Cascino GD; Jack CR Jr; Parisi JE; Marsh WR; Kelly PJ; Sharbrough FW; Hirschorn KA; Trenerry MR
1992 Mar;11(1):51-59, Epilepsy research
We performed magnetic resonance imaging (MRI) using a high-field strength magnet (1.5 T) in two series of 53 patients with intractable partial epilepsy of frontal lobe or temporal lobe origin who subsequently received ablative surgery for their seizure disorder. In the first series of patients the pathologic correlation and prognostic importance of an MRI-identified lesion in the frontal lobe were assessed. Twenty-five percent of the patients with negative MRI studies and 67% of patients with neuroimaging abnormalities restricted to the frontal lobe, were seizure-free at a minimum duration of follow-up of 1 year. None of the patients with a multilobar MRI-detected abnormality was seizure-free postoperatively. In the second study the sensitivity and specificity of MRI-based hippocampal volumetry was determined in pediatric patients with partial epilepsy of temporal lobe origin unrelated to foreign-tissue pathology. Hippocampal formation atrophy in the epileptic temporal lobe was identified in 63% of patients. The sensitivity and specificity of hippocampal volumetry was 100% in patients with mesial temporal sclerosis. The presence of an MRI-detected epileptogenic lesion in the frontal lobe and hippocampal formation atrophy in the temporal lobe may correlate with the underlying pathology and affect the identification of potential candidates for epilepsy surgery
— id: 33652, year: 1992, vol: 11, page: 51, stat: Journal Article,

Long-term follow-up of stereotactic lesionectomy in partial epilepsy: predictive factors and electroencephalographic results
Cascino GD; Kelly PJ; Sharbrough FW; Hulihan JF; Hirschorn KA; Trenerry MR
1992 Jul-Aug;33(4):639-644, Epilepsia
We performed an extended follow-up study assessing the efficacy of stereotactic lesionectomy in 23 patients with foreign-tissue lesions and intractable partial epilepsy. Sixteen lesions involved functional or eloquent cortex as determined by anatomic localization. By definition, the surgical objective in these patients was excision of the lesion, and not the surrounding cerebral cortex. The mean duration of follow-up was 48.5 months (range 26-69 months). Seventeen patients (74%) had a significant reduction in seizures (greater than or equal to 90%) after lesionectomy. Thirteen patients (56%) had a class I operative outcome (seizure-free, single seizure episode, or auras only). Five of these patients were successfully discontinued from antiepileptic drug (AED) therapy. Patients with temporal lobe lesions were statistically less likely to be rendered seizure-free (p less than 0.05). Age at operation, duration of epilepsy, and underlying pathology were not significant predictors of seizure outcome. The anatomic distribution of extracranial EEG recorded epileptiform activity did not appear to be an important determinant of outcome. The absence of interictal epileptiform activity in the 3-month postoperative EEG correlated with a significant reduction in seizures. Long-term follow-up indicates that lesionectomy may be effective in select patients with medically refractory partial seizure disorders
— id: 33651, year: 1992, vol: 33, page: 639, stat: Journal Article,

Computer-assisted stereotactic third ventriculostomy in the management of noncommunicating hydrocephalus
Dalrymple SJ; Kelly PJ
1992 ;59(1-4):105-110, Stereotactic & functional neurosurgery
Between January, 1984, and December, 1990, a total of 85 patients have undergone stereotactic third ventriculostomy (TV) at the Mayo Clinic. Sixty-one patients (74%) presented with mass lesions in the region of the posterior third ventricle, aqueduct of Sylvius or fourth ventricle. Twenty-four patients (26%) presented with non-tumoral, adult/adolescent-onset aqueductal stenosis. Follow-up was available for all 85 patients and ranged from 1 to 66 months (mean 25 months). Follow-up revealed initial patency in 84 patients. Eleven patients (13%) ultimately required extracranial shunting for persistent symptomatic hydrocephalus. Two patients underwent revision of their TV. Twenty-seven patients had been previously shunted. Of these, 23 (85%) have remained asymptomatic after TV without the need for further shunting. Stereotactic TV is a safe and effective way of re-establishing normal cerebrospinal fluid flow dynamics in selected cases of obstructive hydrocephalus
— id: 33656, year: 1992, vol: 59, page: 105, stat: Journal Article,

The symptomatic and functional outcome of stereotactic thalamotomy for medically intractable essential tremor
Goldman MS; Ahlskog JE; Kelly PJ
1992 Jun;76(6):924-928, Journal of neurosurgery
Eight patients with medically refractory disabling essential tremor underwent ventralis lateralis (VL) thalamotomies; the procedure was unilateral in seven cases and bilateral (staged) in the other. Contralateral tremor remained absent or markedly reduced in all patients at the time of the most recent follow-up examinations, at a mean of 17.3 months after surgery. Disability was determined by a modified form of an established rating scale for tremor, and was reduced from a mean score of 21.1 (moderate grade) to 3.9 (absent grade) (p less than 0.001). Interestingly, voice tremor was abolished or significantly improved in 71.4% of patients with preoperative voice tremor. This feature has not been reported previously. Persistent surgical morbidity was limited to two patients with mild dysarthria and one with a mild cognitive impairment. There were no surgically related deaths. It is concluded that stereotactic VL thalamotomy is a treatment option for medically intractable disabling essential tremor
— id: 33665, year: 1992, vol: 76, page: 924, stat: Journal Article,

Stereotactic thalamotomy for medically intractable essential tremor
Goldman MS; Kelly PJ
1992 ;58(1-4):22-25, Stereotactic & functional neurosurgery
Objective surgical symptomatic outcome of ventrolateral (VL) thalamotomy specifically for essential tremor is uncommonly reported and functional outcome has not been investigated previously. In the present series, 7 patients underwent unilateral and 1 patient staged bilateral VL thalamotomies for disabling medically refractory essential tremor. At follow-up examination (mean 17.3 months, range 1-50 months), all patients enjoyed complete ablation or significant amelioration of the targeted tremor. Disability as determined by a modified form of an established rating scale for tremor was reduced from moderate (57%) or severe (43%) to absent (86%) or mild (14%). Interestingly, voice tremor was ablated or significantly improved in 71.4% of patients with preoperative voice tremor
— id: 33666, year: 1992, vol: 58, page: 22, stat: Journal Article,

Symptomatic and functional outcome of stereotactic ventralis lateralis thalamotomy for intention tremor
Goldman MS; Kelly PJ
1992 Aug;77(2):223-229, Journal of neurosurgery
In the past, intention tremor has responded well to selected neuroablative procedures; however, objective symptomatic and functional outcomes of ventralis lateralis (VL) thalamotomy specifically for intention tremor in the post-computerized tomography era has rarely been reported. This series explored the symptomatic and functional impact of VL thalamotomy on 14 patients presenting at the Mayo Clinic with severe, refractory intention tremor due to multiple sclerosis (five patients), trauma (four patients), or stroke (five patients). General neurological examinations, psychometric evaluations, speech pathology assessments, and neuroradiological scans were performed. Pre- and postoperative disability were graded according to a modified form of an established rating scale for tremor. All patients received VL radiofrequency thalamotomies utilizing neurophysiological recording and stimulation control. Contralateral targeted upper-extremity tremor remained symptomatically absent or markedly reduced in 81.8% of cases (mean follow-up period 23.4 months). The median disability score was reduced by 12 points (0.02 less than p less than 0.05). Persistent surgical morbidity was limited to two patients with mild, nondisabling dysarthrias. One elderly patient died of pulmonary complications 2 weeks postoperatively. There were no reported surgically induced exacerbations in multiple sclerosis; however, some of these patients exhibited difficulties with electrophysiological localization. These results compare favorably with those reported in the literature and confirm that stereotactic VL thalamotomy for debilitating intention tremor carries a low surgical risk and can be an effective treatment option for properly selected patients
— id: 33664, year: 1992, vol: 77, page: 223, stat: Journal Article,

Distribution of transforming growth factor-beta 1 in human astrocytomas
Horst HA; Scheithauer BW; Kelly PJ; Kovach JS
1992 Nov;23(11):1284-1288, Human pathology
We used immunohistochemical techniques to study the distribution of transforming growth factor-beta 1 (TGF-beta 1) and infiltrating lymphocytes and macrophages in human astrocytomas. Thirteen of 15 grade 4 astrocytomas (glioblastomas) showed staining with anti-TGF-beta 1 antibody, predominantly in proliferating endothelial complexes and surrounding small and medium-sized blood vessels. Brain tissue microscopically free of tumor cells (n = 8) and more differentiated astrocytomas of varying grade (1 to 3; n = 6) devoid of endothelial proliferation did not stain with anti-TGF-beta 1. Normal brain contained only rare lymphoreticular cells. The majority of astrocytomas studied, however, contained T lymphocytes and macrophages with smaller numbers of B lymphocytes. The lymphoreticular infiltrates were concentrated primarily in close proximity to blood vessels. Within an individual tumor perivascular regions staining for TGF-beta 1 never contained more than occasional T lymphocytes. Perivascular regions not staining for TGF-beta 1 frequently contained low to high numbers of T lymphocytes. The inverse relationship in the distribution of TGF-beta 1 and lymphocyte infiltrates is compatible with a functional relationship between this cytokine and an immune effector cell response to glioblastomas
— id: 33679, year: 1992, vol: 23, page: 1284, stat: Journal Article,

A new multimodality correlative imaging technique for VOP/VIM (VL) thalamotomy procedures
Kall BA; Goerss SJ; Kelly PJ
1992 ;58(1-4):45-51, Stereotactic & functional neurosurgery
This paper describes our experience at Mayo Clinic with a new technique for planning ventro-oralis posterior (VOP) ventral intermediate (ventrolateral) VIM (VL) thalamotomy procedures for selected patients with medically intractable tremor. This new method employs a multimodality correlative imaging technique for determining the lesion target point on MR images. At surgery, stereotactic frame settings for the final lesion target were ultimately determined by stereotactic ventriculography modified by neurophysiological recording. Acceptable correlation was found between the multimodality correlative imaging method and the actual target coordinates determined by ventriculography and semi-microelectrode recording
— id: 33701, year: 1992, vol: 58, page: 45, stat: Journal Article,

Stereotactic resection and its limitations in glial neoplasms
Kelly PJ
1992 ;59(1-4):84-91, Stereotactic & functional neurosurgery
With imaging-based volumetric stereotactic techniques, it is possible to selectively and accurately remove any CT- or MRI-defined part or all of any intra-axial neoplasm. However, glial neoplasms are composed of two elements: tumor tissue and isolated tumor cells which infiltrate brain parenchyma. In high-grade gliomas and pilocytic astrocytomas, the tumor tissue component is most accurately defined by the volume of contrast enhancement. Tumor tissue in low-grade nonpilocytic gliomas is indistinguishable on imaging from infiltrated parenchyma. Stereotactic biopsy is presently the only method by which CT hypodense tumor tissue can be differentiated from infiltrated parenchyma, which is also hypodense. In eloquent brain areas, stereotactic resection is appropriate for the tumor tissue component only in patients harboring glial tumors
— id: 33777, year: 1992, vol: 59, page: 84, stat: Journal Article,

[Carbon dioxide laser and stereotaxic craniotomy]
Kelly PJ; Regli L; al-Rodhan NR
1992 ;38(4):208-216, Neurochirurgie
This article describes the development and contemporary clinical applications for a computer interactive volumetric stereotactic system in CT and/or MRI-based resection of superficial and deep seated intracranial lesions. The carbon dioxide laser was found to be particularly useful in the resection of deep seated lesions by this volumetric stereotactic method for three reasons: 1) the CO2 laser is a convenient tool for removing tissue from the depths of a deep cavity, 2) it is relatively hemostatic, and 3) the precision provided by the CO2 laser renders it safer than other methods for dissecting tumors from important brain tissue, e.g. the internal capsule. The specific clinical methods of the technique: data acquisition, computer based surgical planning, and interactive stereotactic open surgery are discussed. The clinical experience in 500 consecutive cases in the resection of various lesions from specific anatomical areas is presented. Total overall morbidity was 7% and mortality 1%. We have found the technique of most benefit in the resection of histologically circumscribed intra-axial lesions
— id: 33674, year: 1992, vol: 38, page: 208, stat: Journal Article,

Computers in stereotactic neurosurgery
Kelly, Patrick J.; Kall, Bruce A
Boston : Blackwell Scientific Publications, 1992,
— id: 395, year: 1992, vol: , page: , stat: ,

Prognostic value of cytogenetic analysis in human cerebral astrocytomas
Kimmel DW; O'Fallon JR; Scheithauer BW; Kelly PJ; Dewald GW; Jenkins RB
1992 May;31(5):534-542, Annals of neurology
Cytogenetic analysis has become an important part of the diagnostic evaluation of most hematological neoplasms. However, there is limited information on the value of cytogenetic analysis in most solid tumors, including cerebral astrocytomas. This report summarizes a prospective cytogenetic study of 99 human cerebral astrocytomas, 16 mixed oligoastrocytomas, and 2 gliosarcomas. The cytogenetic procedure involved in situ culture and robotic harvesting techniques. Correlative clinical and survival data were available on all patients. We successfully cultured and obtained suitable metaphases in 107 of the 117 tumors. One or more chromosomally abnormal clones were observed in 72 tumors, and nonclonal or normal karyotypes were observed in 35 tumors. In a multivariate analysis, survival time was significantly better in patients whose tumors had normal or nonclonal karyotypes on cytogenetic analyses than in those whose tumors had clonal abnormalities (p = 0.0071). Our study demonstrates that cytogenetic analysis provides independent prognostic information in patients with cerebral astrocytomas
— id: 33682, year: 1992, vol: 31, page: 534, stat: Journal Article,

Computer-assisted stereotactic biopsy and volumetric resection of thalamic pilocytic astrocytomas. Report of 23 cases
Lyons MK; Kelly PJ
1992 ;59(1-4):100-104, Stereotactic & functional neurosurgery
Twenty-three cases of pathologically verified thalamic pilocytic astrocytomas diagnosed at computer-assisted stereotactic biopsy and/or volumetric resection at the Mayo Clinic between January 1985 and October 1990 were reviewed. Computer-assisted stereotactic volumetric resection was performed in 19 patients. Postoperative imaging demonstrated no residual contrast-enhancing tumor in 14 patients and a small amount of contrast-enhancing tumor (less than 5% of the original tumor volume) in 5 patients. Biopsy only was performed in 4 patients: 2 with primarily cystic tumors successfully treated with stereotactic instillation of 32P, and 2 patients with stable (nonprogressive) deficits. There was 1 operative death; a patient with tumor extending into the midbrain became comatose and died 10 days after surgery. The remaining 22 patients are alive and well. Computer-assisted stereotactic volumetric resection of thalamic pilocytic astrocytomas can be performed with low morbidity and a favorable long-term prognosis
— id: 33727, year: 1992, vol: 59, page: 100, stat: Journal Article,

[Stereotaxic biopsy for primary lymphomas of the central nervous system]
Meneses MS; O'Neill BP; Kelly PJ
1992 Sep;50(3):319-323, Arquivos de neuro-psiquiatria
Primary lymphomas of the CNS are rare. However the incidence of these lesions has increased recently. These tumors are often situated in the thalamus and basal ganglia, but can be multifocal. The treatment for primary CNS lymphoma is radiotherapy alone or in association with chemotherapy. Because the associated morbidity is very low stereotactic biopsy is an ideal method for determining the histologic diagnosis in patients with suspected CNS lymphoma. The authors present a study of 49 patients with primary CNS lymphomas in which a stereotactic biopsy was performed
— id: 33725, year: 1992, vol: 50, page: 319, stat: Journal Article,

Cytogenetic and loss of heterozygosity studies in ependymomas, pilocytic astrocytomas, and oligodendrogliomas
Ransom DT; Ritland SR; Kimmel DW; Moertel CA; Dahl RJ; Scheithauer BW; Kelly PJ; Jenkins RB
1992 Nov;5(4):348-356, Genes, chromosomes & cancer
Cytogenetic and/or loss of heterozygosity studies were performed on 13 ependymomas, 11 pilocytic astrocytomas, and 18 oligodendrogliomas. Loss of chromosome 22 was the most frequent genetic abnormality among the ependymomas. We found no consistent genetic abnormality in pilocytic astrocytomas. The most common genetic abnormality in oligodendrogliomas was loss of a portion of chromosome 19. Each informative oligodendroglioma had loss of alleles mapped to the long arm (q) of chromosome 19. One oligodendroglioma had an apparent homozygous deletion of the D19S8 locus. Our results, when combined with those in the literature, indicate that chromosomes 9, 11, and 22 may harbor genes important for the pathogenesis of ependymomas and that 19q probably harbors a gene important for the pathogenesis of oligodendrogliomas
— id: 33681, year: 1992, vol: 5, page: 348, stat: Journal Article,

Correlation of cytogenetic analysis and loss of heterozygosity studies in human diffuse astrocytomas and mixed oligo-astrocytomas
Ransom DT; Ritland SR; Moertel CA; Dahl RJ; O'Fallon JR; Scheithauer BW; Kimmel DW; Kelly PJ; Olopade OI; Diaz MO; et al.
1992 Nov;5(4):357-374, Genes, chromosomes & cancer
The aims of this study were to correlate cytogenetic studies and molecular genetic loss of heterozygosity (LOH) analyses in human astrocytomas and mixed oligo-astrocytomas, and to locate putative tumor suppressor genes on chromosome 10. Paired blood and tumor samples from 53 patients were analyzed. The tumors included 45 diffuse astrocytomas (39 grade 4, 4 grade 3, and 2 grade 2), 1 astroblastoma, and 7 mixed oligo-astrocytomas (2 grade 4, 4 grade 3, and 1 grade 2). By cytogenetic analyses the most common numeric chromosome abnormalities were +7, -10, -13, -14, -17, +19, -22, and -Y. The most common structural abnormalities involved chromosome arms 1p, 1q, 5p, and 9p. By LOH and dosage analysis the most common molecular genetic abnormalities were of chromosome arms 5p, 6p, 7q, 9p, 10p, 10q, 13q, 14q, 17p, and 19p. When the results of all methods were combined, the most commonly abnormal chromosomes were, in descending frequency, 10, Y, 17, 7, 13, and 9. In 80 percent of cases the cytogenetic and molecular genetic studies were concordant. LOH studies were more sensitive in detecting loss of genetic material than cytogenetic analyses and accounted for 60% of the discordant results. When there were structural abnormalities, such as translocations or inversions, cytogenetic analysis was more sensitive in detecting an abnormality than molecular genetic studies. In addition to the 24 tumors which appeared to lose an entire copy of chromosome 10, there were 10 tumors with molecular genetic or cytogenetic evidence of loss of only a portion of chromosome 10. The genetic analyses of these tumors suggest that there are 2 regions on chromosome 10 that may contain potential tumor suppressor genes. One lies distal to locus D10S22 from 10q22 to 10qter, and the other lies proximal to locus TST1 on the 10q arm near the centromere or on the 10p arm
— id: 33680, year: 1992, vol: 5, page: 357, stat: Journal Article,

Reduced D2 dopamine and muscarinic cholinergic receptor densities in caudate specimens from fluctuating parkinsonian patients
Ahlskog JE; Richelson E; Nelson A; Kelly PJ; Okazaki H; Tyce GM; van Heerden JA; Stoddard SL; Carmichael SW
1991 Aug;30(2):185-191, Annals of neurology
Binding of spiperone and 3-quinuclidinyl benzilate (QNB), both labeled with hydrogen 3 (3H), were measured in caudate tissue obtained from 8 living parkinsonian patients at the time of cerebral transplantation. This was clinically homogeneous group of patients. All remained predominantly responsive to levodopa, although with marked disability secondary to clinical fluctuations (short-duration responses) and medication-induced dyskinesias; all were receiving substantial doses of levodopa and 6 of the 8 patients were additionally receiving bromocriptine or pergolide. Binding densities of dopamine D2 receptors, as measured by [3H]spiperone binding, were reduced in this group of patients, compared to caudate specimens from autopsy control subjects. This findings may reflect medication-induced receptor downregulation. Parallel changes occurred with muscarinic cholinergic receptors; [3H]QNB binding was significantly reduced, compared to autopsy control values. This reduction of muscarinic receptors might be due to loss of nigrostriatal terminals that are known to contain muscarinic receptors. Alternatively, muscarinic receptors may have been downregulated by increased corticostriatal glutamatergic input to cholinergic cells, inferred to be present based on the prominent levodopa-induced dyskinesias. Finally, receptor deficits could have been a reflection of more widespread degenerative cerebral disease, although levodopa-refractory symptoms were generally not pronounced in these patients
— id: 33657, year: 1991, vol: 30, page: 185, stat: Journal Article,

Stereotactic ventrolateralis thalamotomy for medically refractory tremor in post-levodopa era Parkinson's disease patients
Fox MW; Ahlskog JE; Kelly PJ
1991 Nov;75(5):723-730, Journal of neurosurgery
Thirty-six patients with Parkinson's disease and medically refractory tremor underwent stereotactic ventrolateralis thalamotomy at the Mayo Clinic between 1984 and 1989. All patients had been or were being treated with carbidopa/levodopa but with unsatisfactory tremor control. Modern stereotactic techniques, including microelectrode recording, were used to treat 36 patients, of whom 31 (86%) had complete abolition of tremor and three patients (5%) had significant improvement. Tremor recurred in two patients within 3 months of surgery; however, the remaining patients suffered no recurrence of tremor during follow-up periods ranging from 14 to 68 months (mean 33 months). Persistent complications (arm dyspraxia, dysarthria, dysphasia, or abulia) were noted in five patients but were a source of disability in only two. It is concluded that thalamotomy in carefully selected patients is a beneficial operation for the control of medically refractory parkinsonian resting tremor
— id: 33726, year: 1991, vol: 75, page: 723, stat: Journal Article,

Computer assisted volumetric stereotactic resection of superficial and deep seated intra-axial brain mass lesions
Kelly PJ
1991 ;52(6):26-29, Acta neurochirurgica. Supplementum
The integrated computer-based stereotactic system for volumetric resection of brain mass lesions, which has been developed by the author, is described. The results of a series of 451 cases are presented. Morbidity was 7.7% and mortality 1%
— id: 33776, year: 1991, vol: 52, page: 26, stat: Journal Article,

Stereotactic third ventriculostomy in patients with nontumoral adolescent/adult onset aqueductal stenosis and symptomatic hydrocephalus
Kelly PJ
1991 Dec;75(6):865-873, Journal of neurosurgery
Sixteen consecutive patients with obstructive hydrocephalus due to nontumoral aqueductal stenosis of adolescent or adult onset underwent computerized tomography-guided stereotactic third ventriculostomy. Computer-assisted angiographic target-point cross-registration was used in surgical planning to reduce morbidity. The procedure was used as primary treatment in five previously unshunted patients and in 11 patients who had previously received shunts and who presented when their shunts became obstructed (five patients), became infected (five patients), or required multiple revisions (one patient). At the time of third ventriculostomy, shunt hardware was removed in patients with infected shunts and the distal element of the shunt was ligated in all patients with obstructed shunts except one, who later required repeat third ventriculostomy; the distal shunt was ligated at that time. Follow-up data (range 1 to 5 years, mean 3 1/2 years, after surgery) showed that only one of the 16 patients had undergone a shunting procedure after the third ventriculostomy. The other 15 patients are asymptomatic and shunt-independent. In previously shunt-dependent patients, the peripheral subarachnoid space and cerebrospinal fluid absorption mechanism remained patent in spite of shunts placed earlier. Therefore, in patients with obstructive hydrocephalus due to aqueductal stenosis of adolescent or adult onset, stereotactic third ventriculostomy should be seriously considered as primary surgical management in previously unshunted patients and in shunt-dependent patients with obstructed or infected shunts
— id: 33775, year: 1991, vol: 75, page: 865, stat: Journal Article,

Tumor stereotaxis
Kelly, Patrick J
Philadelphia : Saunders, 1991,
— id: 460, year: 1991, vol: , page: , stat: ,

Posterior fossa ependymomas: report of 30 cases and review of the literature
Lyons MK; Kelly PJ
1991 May;28(5):659-664, Neurosurgery
Thirty patients with histologically confirmed posterior fossa ependymomas operated on between January 1976 and December 1988 were reviewed. The median age was 44 years (range, 1-69 yr). There were 7 children (aged 5 yr or younger) and 23 adults (aged 16 yr or older). There were 18 female patients and 12 male patients. Headache, nausea and vomiting, and disequilibrium were the most frequent symptoms. The most common findings were ataxia and nystagmus. Gross total resection was performed in 8 patients (27%), subtotal resection in 21 patients (70%), and biopsy in only 1 patient (3%). Tumors were low grade in 73% and high grade in 27%. Twenty-seven patients underwent posterior fossa radiotherapy (median dose, 5400 cGy). Fourteen patients also underwent spinal irradiation (median dose, 3520 cGy). Age was the only significant prognostic factor identified (P less than 0.01). The 5-year survival rates were 76% for adults and 14% for children. All 14 patients who died had recurrent or residual tumor at the primary site. This review suggests that in patients with primary posterior fossa ependymomas the following is true: 1) the young patient (5 yr old or younger) has a poor prognosis; 2) there was a trend toward a better 5-year survival rate with a gross total resection; 3) if recurrence occurs, it will be at the primary intracranial site; and 4) symptomatic spinal seeding does not occur frequently
— id: 33728, year: 1991, vol: 28, page: 659, stat: Journal Article,

Transforming growth factor-alpha, epidermal growth factor receptor, and proliferating potential in benign and malignant gliomas
Maruno M; Kovach JS; Kelly PJ; Yanagihara T
1991 Jul;75(1):97-102, Journal of neurosurgery
Surgical specimens from six benign and 16 malignant human gliomas were investigated immunohistochemically to correlate the degree of malignancy, the distribution of transforming growth factor-alpha (TGF-alpha) and epidermal growth factor (EGF) receptor, and the potential for cell proliferation using monoclonal antibodies to TGF-alpha, EGF receptor, and Ki-67. Fourteen (88%) of the malignant gliomas and one (17%) of the benign gliomas were found to be positive for TGF-alpha, and 14 (88%) of the malignant gliomas and two (33%) of the benign gliomas expressed EGF receptor. The proliferation index with Ki-67 was 18.8% +/- 8.1% (mean +/- standard deviation) in malignant gliomas and 1.9% +/- 1.8% in benign gliomas. In general, cells positive for EGF receptor and Ki-67 were randomly distributed throughout the tumor tissue, and cells positive for TGF-alpha tended to be clustered without obvious relationship to areas of necrosis or blood vessels. In some tumors, cells positive for TGF-alpha, EGF receptor, and Ki-67 were associated in a focal distribution. The more frequent expression of TGF-alpha and EGF receptor in the highly proliferative malignant gliomas is compatible with a role for TGF-alpha and EGF receptor in the induction or stimulation of malignant gliomas
— id: 33636, year: 1991, vol: 75, page: 97, stat: Journal Article,

Is colloid cyst of the third ventricle a manifestation of nevoid basal cell carcinoma syndrome?
Nishino H; Gomez MR; Kelly PJ
1991 Sep;13(5):368-370, Brain & development (Tokyo)
A 14-year-old girl with nevoid basal cell carcinoma syndrome presented with intermittent headache and nausea. Magnetic resonance imaging and a computed tomographic scan of the head revealed a colloid cyst of the third ventricle and mild dilatation of the lateral ventricle. The cyst was successfully removed by stereotaxic surgery. The occurrence of two rare disorders in the same patient could be a coincidence. Other similar patients must be found before it is established that the colloid cyst is part of the nevoid basal cell carcinoma syndrome
— id: 33672, year: 1991, vol: 13, page: 368, stat: Journal Article,

Sequential magnetic resonance imaging following stereotactic radiofrequency ventralis lateralis thalamotomy
Tomlinson FH; Jack CR Jr; Kelly PJ
1991 Apr;74(4):579-584, Journal of neurosurgery
Serial postoperative magnetic resonance (MR) studies were obtained in 21 patients who underwent somatotopically placed stereotactic radiofrequency (rf) ventralis lateralis thalamotomy for the control of movement disorders. The MR studies were reviewed to determine the MR characteristics of early-phase (less than or equal to 7 days) and late-phase (8 days to 5 months) lesions. Surgery was performed for the control of parkinsonian tremor (14 cases), intention tremor (six cases), and essential tremor (one case). Single rf lesions were made with an electrode (1.6 mm in diameter, 3 mm in tip length) heated to 78 degrees C for 60 seconds. On MR images of the lesions, three distinct concentric zones were identified, described as follows (from the center outward). Zone 1 gives increased signal on long-relaxation time (TR) (T2-weighted) MR images in early- and late-phase lesions and decreased signal on short-TR (T1-weighted) MR images in early-phase lesions only. Zone 2 gives decreased signal on long-TR (T2-weighted) images in early- and late-phase lesions; it gives isointense signal on short-TR (T1-weighted) images in early-phase lesions only. Zone 3 gives increased signal on long-TR (T2-weighted) images in early-phase lesions only and decreased signal on short-TR (T1-weighted) MR images in early-phase lesions only. It is considered that in early-phase lesions, Zone 2, with a mean diameter of 7.3 mm on axial long-TR (T2-weighted) imaging, represents an area of hemorrhagic coagulation necrosis. In late-phase lesions, Zone 2, with a mean diameter of 5.0 mm on axial long-TR (T2-weighted) imaging, represents hemosiderin deposition. Zone 3 likely represents edema, and this zone disappears between the early and late periods. From regression analysis, lesion size began to stabilize at approximately 7 months with a mature lesion diameter of 3.3 mm. Long-term follow-up monitoring (median 16 months) showed good tremor control. Based on clinical and radiological findings, the authors conclude that forms of hemoglobin are suitable markers to assess the size of rf lesions. Serial MR imaging provides a noninvasive means of studying the evolution of rf thalamotomy lesions
— id: 33641, year: 1991, vol: 74, page: 579, stat: Journal Article,

Subependymoma with rhabdomyosarcomatous differentiation: report of a case and literature review
Tomlinson FH; Scheithauer BW; Kelly PJ; Forbes GS
1991 May;28(5):761-768, Neurosurgery
A unique gliomesenchymal neoplasm, consisting of a subependymoma, a form of low-grade glioma, and a rhabdomyosarcoma, is described. It arose and recurred in the brain stem of a 52-year-old man. Immunohistochemical studies demonstrated the presence of a neuroectodermal marker S-100 protein within some sarcoma cells. The occurrence of this rare tumor supports the concept that striated muscle may derive from a neuroectodermal precursor lesion
— id: 33640, year: 1991, vol: 28, page: 761, stat: Journal Article,

Adrenal medullary transplantation into the brain for treatment of Parkinson's disease: clinical outcome and neurochemical studies
Ahlskog JE; Kelly PJ; van Heerden JA; Stoddard SL; Tyce GM; Windebank AJ; Bailey PA; Bell GN; Blexrud MD; Carmichael SW
1990 Mar;65(3):305-328, Mayo Clinic proceedings
Transplantation of adrenal medulla into the caudate nucleus as treatment for Parkinson's disease was performed in eight patients. Although our previous 6-month follow-up revealed early modest improvement, an extension of that follow-up to 1 year disclosed no additional gains in any patient. At the end of 1 year, only one patient could be categorized as moderately improved; three patients were mildly improved, and four patients were unimproved. The rationale for transplanting adrenal medulla was to reestablish a physiologic source of dopamine to the striatum. We measured cerebrospinal fluid (CSF) and plasma catecholamines and metabolites before and after transplantation. Conjugated dopamine (the predominant form of dopamine found in the CSF) and homovanillic acid (the major dopamine metabolite) were modestly and inconsistently increased in the CSF. Conjugated and free epinephrine and norepinephrine, as well as 3-methoxy-4-hydroxyphenylglycol concentrations were not increased in CSF after graft placement, an indication that the adrenal chromaffin cells were no longer producing high levels of these nondopamine catecholamines and metabolites. CSF cortisol concentrations were not increased after transplantation, compared with values from controls, consistent with low numbers of functioning adrenal cortical cells contaminating the graft (or poor survival). Posttransplantation CSF did not induce a neurotrophic effect in cell cultures of 15-day embryonic rat dorsal root ganglion or PC12 (rat pheochromocytoma) cell lines. Survival of samples of patients' adrenal medullary tissue for 2 weeks in tissue culture attested to the viability of the graft at the time of transplantation. The relative concentrations of dopamine to epinephrine or norepinephrine increased in these cultured adrenal medullary cells, presumably because of loss of the glucocorticoid influence on catecholamine synthesis. A wide variety of factors could have contributed to our failure to replicate the earlier impressive results of adrenal-to-brain transplantation reported by others. Continued transplantation studies in animal models of parkinsonism are necessary for better elucidation of these factors
— id: 33658, year: 1990, vol: 65, page: 305, stat: Journal Article,

Stereotactic resection of intra-axial cerebral lesions in partial epilepsy
Cascino GD; Kelly PJ; Hirschorn KA; Marsh WR; Sharbrough FW
1990 Aug;65(8):1053-1060, Mayo Clinic proceedings
We performed a retrospective study of stereotactic resections of intra-axial brain mass lesions in 30 patients with intractable partial epilepsy. The most common pathologic alterations observed were vascular malformations (11 lesions) and glial neoplasms (11 lesions). The locations of the lesions included the postcentral gyrus in five patients, the precentral gyrus in five, and the deep-seated left posterior temporal region in four, all of which were sites that may have precluded standard craniotomy and cortical resection. Of the 30 medically refractory patients, 26 had at least an 80% reduction in seizure activity at a mean duration of follow-up of 22 months postoperatively. Nineteen of 22 patients with at least 1 year (mean, 28 months) of follow-up and 13 of 15 patients with at least 2 years (mean, 34 months) of follow-up had favorable surgical outcomes. 'Lesionectomy' may allow pathologic examination of intracranial lesions and may produce a worthwhile reduction in seizure activity in some patients with intractable partial epilepsy
— id: 33654, year: 1990, vol: 65, page: 1053, stat: Journal Article,

Stereotactic resection of occult vascular malformations
Davis DH; Kelly PJ
1990 May;72(5):698-702, Journal of neurosurgery
Angiographically occult vascular malformations can be identified on computerized tomography and magnetic resonance imaging. Surgical excision, when possible, is the treatment of choice in symptomatic lesions. Because these malformations are usually small and can be located in surgically treacherous areas of the brain, stereotactic resection should be considered. Stereotactic resection of a pathologically verified occult vascular malformation was performed in 26 patients in this series (13 females and 13 males, mean age 30 years). Seventeen patients presented with a seizure disorder, four with an intracerebral hemorrhage, and four with a progressive neurological deficit; one patient was asymptomatic. Sixteen patients had normal neurological examinations, nine had neurological signs referable to their lesion, and one had a visual field deficit related to a previous temporal lobectomy. In six patients evidence of acute hemorrhage was found on imaging studies or at surgery, and 11 patients had evidence of previous hemorrhage on imaging studies, determined at surgery or by histological examination. Three patients had evidence of both acute and previous hemorrhage and six patients had no evidence of hemorrhage. Lesions were located in cortical or subcortical areas in 21 patients, in the thalamus or basal ganglia in three, and in the posterior fossa in two. Following stereotactic resection, 24 patients were improved, one patient was unchanged, and one patient was worse. Without stereotaxis or intraoperative ultrasound studies, localization of these lesions at conventional craniotomy can be difficult. A stereotactic craniotomy is ideally suited to the treatment of these benign circumscribed, but potentially devastating lesions
— id: 33773, year: 1990, vol: 72, page: 698, stat: Journal Article,

Stereotactic craniotomy
Kelly PJ
1990 Oct;1(4):781-799, Neurosurgery clinics of North America
Computed tomography-based stereotactic biopsy procedures for diagnosing intracranial tumors are common today. In addition, point stereotaxis is used to center a craniotomy over a superficial lesion or to find a deep one. Technical innovations have improved performance of these operations. The author describes the instrumentation and current methodology for computer-assisted stereotactic laser microsurgical extirpation of intra-axial lesions and discusses the results
— id: 33774, year: 1990, vol: 1, page: 781, stat: Journal Article,

Cerebral sparganosis. Case report
Mitchell A; Scheithauer BW; Kelly PJ; Forbes GS; Rosenblatt JE
1990 Jul;73(1):147-150, Journal of neurosurgery
The tapeworm Spirometra mansonoides infects man worldwide, particularly in Asian countries. Rarely, the central nervous system is involved; such a case is presented here. In the total of 12 reported cases, including the case described, the worm presented clinically as a mass suspicious for neoplasm or chronic abscess cavity. Surgical removal was invariably curative in each case. Although infrequent, the possibility of tapeworm infection should be entertained in the evaluation of intracranial masses in patients who have visited exotic locales
— id: 33683, year: 1990, vol: 73, page: 147, stat: Journal Article,

Measurement of lumbar CSF levels of met-enkephalin, encrypted met-enkephalin, and neuropeptide Y in normal patients and in patients with Parkinson's disease before and after autologous transplantation of adrenal medulla into the caudate nucleus
Yaksh TL; Carmichael SW; Stoddard SL; Tyce GM; Kelly PJ; Lucas D; van Heerden JA; Ahlskog JE; Byer DE
1990 Mar;115(3):346-351, Journal of laboratory & clinical medicine
The levels in lumbar cerebrospinal fluid (CSF) of neuropeptide Y (NPY), methionine enkephalin (Enk), and Enk contained in amino- and carboxy-terminus extended forms (X-Enk) were examined in nine control patients undergoing elective surgical procedures and in eight patients with advanced Parkinson's disease, before and after the autologous transplantation of adrenal medullary fragments into the right caudate nucleus. The levels of CSF Enk and X-Enk before surgery in patients with Parkinson's disease were significantly less than those observed in control patients (Enk, 166 +/- 38 vs 264 +/- 44 pg/ml; X-Enk, 794 +/- 416 vs 1497 +/- 153 pg/ml). NPY levels did not differ (221 +/- 25 vs 193 +/- 23 pg/ml). After surgery, lumbar CSF samples were taken at 6 weeks, 12 weeks, 6 months, and 9 months. Placement of adrenal medullary fragments into the striatum had no effect on the levels of NPY or Enk at any time point. The levels of X-Enk were significantly enhanced only at 12 weeks (1138 +/- 140 pg/ml) but were at presurgical levels again by 6 months. These data suggest that the transplant was not functionally contributing to the CSF levels of these peptides
— id: 33659, year: 1990, vol: 115, page: 346, stat: Journal Article,

Stereotaxic suboccipital transcerebellar biopsy of pontine mass lesions
Abernathey CD; Camacho A; Kelly PJ
1989 Feb;70(2):195-200, Journal of neurosurgery
Twenty-six patients (16 male and 10 female) ranging in age from 5 to 68 years underwent suboccipital transcerebellar stereotaxic biopsy of mass lesions situated in the pons. Stereotaxic computerized tomography, magnetic resonance imaging, and angiographic data were obtained while the patient was positioned in an inverted custom stereotaxic head frame. The patients were then placed under general endotracheal anesthesia and positioned prone. Optimal trajectory planning utilized a transcerebellar route directed through the middle cerebellar peduncle, with target and entry points calculated to avoid vascular structures. No complications were encountered in the perioperative period when this technique was used. Histological diagnosis of the lesions revealed: astrocytomas in 14 patients, oligodendroglioma in one, ependymoma in one, arteriovenous malformations in two, radionecrosis in one, cryptococcal abscess in one, demyelinating disease in three, and infarctions in three. No consistent correlation could be made between radiographic characteristics and histological diagnoses. Empiric treatment of brain-stem lesions without tissue diagnosis based upon the radiological and clinical findings may result in inappropriate therapy administration. Alternatively, open operative procedures to obtain tissue require a visible surface abnormality to guide biopsy, and carry the risks of a major surgical procedure in already compromised patients. For these reasons the authors consider a suboccipital transcerebellar stereotaxic biopsy to be the diagnostic procedure of choice in the assessment of pontine mass lesions
— id: 33696, year: 1989, vol: 70, page: 195, stat: Journal Article,

Treatment of colloid cysts of the third ventricle by stereotaxic microsurgical laser craniotomy
Abernathey CD; Davis DH; Kelly PJ
1989 Apr;70(4):525-529, Journal of neurosurgery
The therapeutic strategies employed in the management of anterior third-ventricular mass lesions remain controversial. Resection by conventional craniotomy, whether via a transcallosal or transcortical approach, carries well-known risks and limitations. Alternatively, in this region traditional stereotaxy has been relegated to use with biopsy only or cyst aspiration procedures. Combining aspects of both conventional and stereotaxic techniques has allowed total removal of 12 colloid cysts in six women and six men ranging in age from 25 to 71 years. No mortality and minimal morbidity have been associated with the procedures. There has been no evidence of recurrence in an average follow-up period of 19 months. By coupling the benefits of stereotaxic precision and localization to the microsurgical management of colloid cysts, several rewards have been realized: 1) only a limited cortical dissection is needed; 2) the hazards of callosal or forniceal injury can be avoided; 3) the lesion is easily localized regardless of ventricular size; 4) hemostasis can be readily achieved with bipolar cautery or defocused laser power; and 5) most importantly, a total resection is possible with little risk to the patient. Stereotaxic microsurgical laser craniotomy provides a new option for the management of colloid cysts and other anterior third-ventricular lesions
— id: 33731, year: 1989, vol: 70, page: 525, stat: Journal Article,

Cerebrospinal fluid indices of blood-brain barrier permeability following adrenal-brain transplantation in patients with Parkinson's disease
Ahlskog JE; Tyce GM; Kelly PJ; van Heerden JA; Stoddard SL; Carmichael SW
1989 Aug;105(2):152-161, Experimental neurology
Cerebrospinal fluid (CSF) and serum or plasma concentrations of albumin, IgG and carbidopa were measured before and after adrenal-brain transplantation in patients with Parkinson's disease to indirectly assess blood-brain barrier (BBB) integrity. Previous studies in animals have suggested that the BBB is compromised by cerebral transplantation. CSF and plasma levodopa was also measured to permit comparison with the carbidopa values, recognizing that levodopa readily crosses the BBB via facilitated transport. Our patients underwent adrenal-brain transplantation in accordance with the method of Madrazo et al. (I. Madrazo, R. Drucker-Colin, V. Diaz, J. Martinez-Mata, C. Torres, and J. J. Becerril, 1987, N. Engl. J. Med. 316: 831-834) in which adrenal medullary pieces are implanted in the head of the caudate nucleus, in contact with the cerebrospinal fluid. All patients were maintained on oral carbidopa/levodopa therapy after surgery. CSF albumin/serum albumin and CSF IgG/serum IgG ratios were initially elevated above the preoperative baseline 6 weeks after the surgery; however, these values returned to the preoperative baseline by 6 months following the operation in six of seven patients. This suggested that the BBB was sufficiently intact to exclude these larger protein molecules from the CSF of these six patients. On the other hand, exogenously administered carbidopa, which normally is largely excluded from the cerebrospinal fluid by the BBB, was modestly increased in the CSF in four of the five patients in which it was measured. This suggests that the transplant BBB might be partially patent to small molecules for at least 6 months after the surgery. Whether increased passage of carbidopa into CSF and perhaps the transplant is of clinical significance has yet to be determined. Median CSF levodopa did not increase after surgery, probably because a limited defect in the BBB would be likely to be overshadowed by the effects of facilitated transport. CT scans performed following intravenous iothalamate meglumine contrast failed to reveal enhancement (dye leakage) near the transplantation site; however, artifact from the metal surgical clips used in the Madrazo procedure prevented good visualization of the area
— id: 33661, year: 1989, vol: 105, page: 152, stat: Journal Article,

Colloid cysts: experience with the management of 84 cases since the introduction of computed tomography
Camacho A; Abernathey CD; Kelly PJ; Laws ER Jr
1989 May;24(5):693-700, Neurosurgery
A retrospective review of colloid cysts diagnosed from 1974 to 1986 emphasizes the presenting symptoms of these lesions, their surgical management, and the contribution of modern imaging techniques to their diagnosis and therapy. In this 12-year period, 84 patients (45 men and 39 women) had a colloid cyst diagnosed. The patients' mean age was 46 years (range, 7-82 years). Surgery was performed in 55 patients, 7 of whom had undergone prior surgery elsewhere. The surgical approaches used were transfrontal-transventricular, transcallosal, computer-assisted stereotactic aspiration and resection by stereotactic craniotomy, and shunting of cerebrospinal fluid without removal of the lesion. There was no operative mortality, but complications occurred in 15 patients (27%). Preoperative imaging showed hydrocephalus in 93% of the patients: severe in 43%, moderate in 36%, and mild in 14%. In the surgically treated group, the most common presenting symptoms were headache, change in mental status, ataxia, nausea and vomiting, visual disturbance, emotional lability/inappropriate affect, depersonalization, and hypersomnolence. Twenty-four patients for whom surgery was not recommended are being followed up closely. Most of these patients had normal ventricles. The symptoms in this group included headache, anxiety/nervousness, ataxia, memory impairment, visual disturbance, and seizures. Five autopsy cases of patients with colloid cysts were available during this period and were reviewed. Direct removal of colloid cysts can be accomplished with low morbidity and mortality, avoiding the frequent revisions and complications related to shunt procedures. There is a subgroup of colloid cysts that can be operated upon electively or followed up closely with serial imaging studies
— id: 33695, year: 1989, vol: 24, page: 693, stat: Journal Article,

Stereotactic third ventriculostomy: assessment of patency with MR imaging
Jack CR Jr; Kelly PJ
1989 May-Jun;10(3):515-522, AJNR. American journal of neuroradiology
Ventricular CSF signal-intensity characteristics indicative of flowing CSF on MR images (CSF flow void) were analyzed in 20 patients who underwent a CT-based stereotactic third ventriculostomy for presumed internal obstructive hydrocephalus between October 1985 and June 1988. The status of all ventriculostomies was assessed postoperatively by radionuclide ventriculography. Postoperative MR and ventriculographic findings were correlated with the patients' subsequent clinical course. A CSF flow void in the anterior and inferior third ventricle, which seems to indicate vigorous pulsatile CSF flow through a functioning ventriculostomy, was present in all 19 patients who were clinically improved after ventriculostomy. In all 19 of these patients the radionuclide ventriculogram demonstrated normal CSF dynamics. One of the 20 patients did not improve postoperatively. The ventriculogram in this patient revealed delayed ventricular clearing and impaired CSF resorption, and the postoperative MR image did not demonstrate an anterior/inferior third ventricular CSF flow void. Eight of these patients were evaluated preoperatively by MR; one of these eight was the single nonimproved individual. None of the eight preoperative MR studies demonstrated a CSF flow void in the anterior/inferior third ventricle; however, this finding was present in seven of seven postoperative MR studies in clinically improved patients. We conclude that the presence of a CSF flow void in the anterior/inferior third ventricle on a postoperative MR examination is sufficient to document patency of a third ventriculostomy. The absence of this finding may be due to a nonpatent ventriculostomy or perhaps an extraventricular CSF obstruction. The more invasive ventriculogram may be reserved for this situation to distinguish between these latter two possibilities
— id: 33730, year: 1989, vol: 10, page: 515, stat: Journal Article,

A cytogenetic study of 53 human gliomas
Jenkins RB; Kimmel DW; Moertel CA; Schultz CG; Scheithauer BW; Kelly PJ; Dewald GW
1989 Jun;39(2):253-279, Cancer genetics & cytogenetics
Cytogenetic studies were performed on human glioma samples obtained by stereotactic biopsy, stereotactic craniotomy, or routine craniotomy. Using in situ culture and robotic harvesting techniques, we obtained suitable metaphases in 50 (94%) of 53 tumors, including 28 diffuse astrocytomas, four juvenile pilocytic astrocytomas, two gliosarcomas, three other miscellaneous astrocytomas, eight oligodendrogliomas, four mixed oligodendroglioma-astrocytomas, and four ependymomas. Cytogenetic studies were performed only on primary cultures; the mean culture time was 9.6 days (range 1-31 days). One or more chromosomally abnormal clones were observed in 35 (66%) tumors. Eleven (21%) other specimens had random nonclonal chromosome abnormalities. In four (8%) specimens, no chromosome abnormalities were noted. The results of this study suggest that grade 3 and 4 tumors are more likely to contain an abnormal clone than tumors of grade 1 or 2 (p less than 0.01). The most common numeric chromosome abnormalities were -6, +7, -10, -13, -14, -15, -18, and -Y. The most common structural abnormalities involved 1p, 6q, 7q, 8p, 9p, 11p, 11q, 13q, and 19q. Four tumors had two or more independent clones and ten contained subclones demonstrating karyotype evolution. With in situ culture and robotic harvesting techniques, cytogenetic studies can be successful on nearly all human gliomas, including those derived from small stereotactic biopsies
— id: 33684, year: 1989, vol: 39, page: 253, stat: Journal Article,

Future perspectives in stereotactic neurosurgery: stereotactic microsurgical removal of deep brain tumors
Kelly PJ
1989 Jan-Mar;33(1):149-154, Journal of neurosurgical sciences
We have developed computer assisted stereotactic methods for the resection of deep seated and centrally located intracranial tumors. Data base acquisition consists of stereotactic computed tomography (CT), magnetic resonance imaging (MRI) and digital angiography (DA). A tumor volume is computer interpolated from CT and MRI defined tumor boundaries. The surgical approach or viewline is selected from stereotactic DA images and anatomically defined by MRI and expressed in mechanical settings on the stereotactic frame. During stereotactic resection the computer displays the position of a stereotactically directed retractor with respect to tumor slices cut perpendicular to the viewline. It is theoretically possible to resect all of the lesion detected by the imaging studies utilizing this method. To date we have performed 267 computer-assisted stereotactic microsurgical resections of a variety of deep seated intracranial tumors with a morbidity rate of 10.5% and mortality rate of 1%. The procedure provides a method by which the surgeon can maintain three dimensional orientation during the resection of CT and MRI defined deep seated intracranial lesions
— id: 33772, year: 1989, vol: 33, page: 149, stat: Journal Article,

Investigative protocols to treat malignant brain tumors in North America
Kelly PJ
1989 Mar;24(3):459-472, Neurosurgery
— id: 33770, year: 1989, vol: 24, page: 459, stat: Journal Article,

Stereotactic biopsy and resection of thalamic astrocytomas
Kelly PJ
1989 Aug;25(2):185-194, Neurosurgery
In this study of 72 patients who had histologically verified thalamic astrocytomas, 44 patients underwent stereotactic serial biopsy, 22 underwent stereotactic resection of the neoplasm, and an additional 6 patients underwent stereotactic biopsy followed by stereotactic resection of the tumor at a later date. Of the 50 patients who underwent stereotactic biopsy, 3 were neurologically worse after the procedure (morbidity, 6%), and 3 additional patients with Grade 4 astrocytomas who preoperatively were rapidly deteriorating neurologically, died within 30 days of the procedure. Of the 28 patients who underwent stereotactic resection, 14 were neurologically improved after the procedure, 10 were unchanged, and 4 were worse. One additional patient died 10 days postoperatively. Thirty-four patients had Grade 4 astrocytomas: 27 underwent stereotactic biopsies. The mean survival after biopsy and irradiation for patients with Grade 4 astrocytomas was 21.4 weeks. The mean survival was 62 weeks in 7 patients with Grade 4 astrocytomas who underwent stereotactic resection and radiation therapy. The mean survival time after biopsy and radiation therapy for patients who had Grade 3 and Grade 2 lesions was 54.4 weeks and 91 weeks, respectively. Twenty-three patients had pilocytic astrocytomas; 8 underwent stereotactic biopsies, and 19 underwent stereotactic resection of the tumor (4 of these underwent biopsy prior to resection). There was no neurological morbidity, but one patient died after resection. Many of those who underwent resection were deteriorating due to an enlarging tumor mass or recurring cyst, and had undergone more conservative therapies such as biopsy and radiation. Even though stereotactic biopsy is appropriate in many patients harboring thalamic astrocytomas, selected patients with significant mass effect from solid tumor or recurring cyst can benefit from stereotactic resection
— id: 33769, year: 1989, vol: 25, page: 185, stat: Journal Article,

Thoralf M. Sundt, Jr
Kelly PJ
1989 Mar;31(3):169-171, Surgical neurology
— id: 33771, year: 1989, vol: 31, page: 169, stat: Journal Article,

Adrenal medullary autograft transplantation into the striatum of patients with Parkinson's disease
Kelly PJ; Ahlskog JE; van Heerden JA; Carmichael SW; Stoddard SL; Bell GN
1989 Mar;64(3):282-290, Mayo Clinic proceedings
In eight patients with advanced Parkinson's disease, we performed autograft transplantation of adrenal medulla to the head of the caudate nucleus. Our technique was similar to that developed by Madrazo and co-workers in Mexico City. No major perioperative complications occurred except for somnolence in one patient for 8 days postoperatively. The follow-up period has been at least 6 months in seven of the patients, and only limited benefit has been apparent. The early morning Parkinson examination score in the 'off' (unmedicated) state was significantly improved in one patient and slightly better in the other six. Diary card entries suggested a mild trend toward improvement (not statistically significant). Four of the seven patients were taking less levodopa 6 months after the operation than they had been preoperatively; three of five patients were no longer taking dopamine agonists postoperatively. We cannot exclude a placebo effect contributing to any of this improvement. A reduction in medication-induced dyskinesia was also noted, but this result may have been due to adjustments in doses or a slightly less potent effect of medication (or both factors). In summary, we have not yet been able to replicate the dramatic success reported for adrenal medullary transplantation by Madrazo's group, although our patients may have experienced mild to moderate improvement. We continue to maintain follow-up surveillance of these patients
— id: 33663, year: 1989, vol: 64, page: 282, stat: Journal Article,

Stereotactic resection of pediatric vascular malformations
Partington MD; Davis DH; Kelly PJ
1989 ;15(5):217-222, Pediatric neuroscience
The technique of computer-assisted stereotactic resection of intra-axial neoplasms can also be used in the treatment of vascular malformations. We report a series of 12 pediatric patients with supratentorial lesions who underwent stereotactic resections between 1985 and 1988. There were 5 boys and 7 girls, with mean age 8 years (range 3-16). Epilepsy was the presenting symptoms in 8 children, hemorrhage in 3, and in 1 the lesion was incidentally diagnosed. Seven lesions were angiographically occult. All lesions were resected without mortality or morbidity. Seizures resolved in 7 of 8 cases, with the remaining patient experiencing a reduction in seizure frequency. Illustrative cases are presented
— id: 33729, year: 1989, vol: 15, page: 217, stat: Journal Article,

Decreased adrenal medullary catecholamines in adrenal transplanted parkinsonian patients compared to nephrectomy patients
Stoddard SL; Ahlskog JE; Kelly PJ; Tyce GM; van Heerden JA; Zinsmeister AR; Carmichael SW
1989 Jun;104(3):218-222, Experimental neurology
Adrenal medullary catecholamines were measured in tissue samples from eight patients who underwent autologous transplantation of the adrenal medulla to the caudate nucleus as a treatment for Parkinson's disease. These adrenal catecholamine levels were compared to a group of patients of similar age who underwent unilateral nephrectomy for renal cell carcinoma. The levels of each catecholamine, expressed as nanomoles per milligram wet weight tissue, were significantly lower (P less than or equal to 0.005) in the parkinsonian patients than in the nephrectomy patients. These observations support data reported previously from autopsy specimens and suggest that the adrenal medullae of parkinsonian patients may be a compromised source of dopamine-producing tissue; this may limit its effectiveness in eliciting maximum clinical improvement following transplantation
— id: 33662, year: 1989, vol: 104, page: 218, stat: Journal Article,

Catecholamines in CSF, plasma, and tissue after autologous transplantation of adrenal medulla to the brain in patients with Parkinson's disease
Tyce GM; Ahlskog JE; Carmichael SW; Chritton SL; Stoddard SL; van Heerden JA; Yaksh TL; Kelly PJ
1989 Aug;114(2):185-192, Journal of laboratory & clinical medicine
Catecholamine concentrations were measured in tissue samples of caudate and adrenal medulla in eight patients with Parkinson's disease who were taking L-dopa and were undergoing autologous transplantation of adrenal medulla to caudate nucleus. High-performance liquid chromatography with electrochemical detection was used for the measurement of analytes. Dopamine concentrations were quite similar in the caudate and the adrenal medulla; epinephrine and norepinephrine concentrations were some 600 times and 90 times higher, respectively, than that of dopamine in adrenal medulla but were barely detectable in caudate nucleus. Catecholamines and metabolites were also measured, before and after transplantation, in lumbar cerebrospinal fluid (CSF) and plasma 1 hour after the patients' first morning dose of L-dopa. The major fractions of the catecholamines in CSF were sulfoconjugated. The concentrations of sulfoconjugated but not free dopamine were modestly increased in CSF after the transplantation, although plasma concentrations were unchanged. CSF concentrations of free and conjugated norepinephrine and epinephrine, 3-methoxy-4-hydroxyphenylglycol, and homovanillic acid were unchanged after the transplantation. The data suggest that the grafted tissue does not retain its noradrenergic or adrenergic properties after transplantation, and that dopamine formation in the brain may be modestly increased. Plasma catecholamines were unaffected after the removal of one adrenal gland for the transplant
— id: 33660, year: 1989, vol: 114, page: 185, stat: Journal Article,

Grading of astrocytomas. A simple and reproducible method
Daumas-Duport C; Scheithauer B; O'Fallon J; Kelly P
1988 Nov 15;62(10):2152-2165, Cancer
This study determines the effectiveness and reproducibility of a previously published method of grading gliomas. The method under study is for use on 'ordinary astrocytoma' cell types, i.e., fibrillary, protoplasmic, gemistocytic, anaplastic astrocytomas and glioblastomas, and is based upon the recognition of the presence or absence of four morphologic criteria: nuclear atypia, mitoses, endothelial proliferation, and necrosis. The method results in a summary score which is translated into a grade as follows: 0 criteria = grade 1, 1 criterion = grade 2, 2 criteria = grade 3, 3 or 4 criteria = grade 4. The histologic material and clinical data were derived from a previously reported series of patients with astrocytomas, radiotherapeutically treated at Mayo Clinic between the years 1960 and 1969. From this series, initially graded 1 to 4, according to the Kernohan system, 287 'ordinary astrocytomas' were entered into the study; 51 pilocytic astrocytomas and microcystic cerebellar-type astrocytomas also were included for comparison. Among ordinary astrocytomas, the grading method under study distinguished 0.7% of grade 1, 17% of grade 2, 18% of grade 3, and 65.3% of grade 4. A 15-year period of follow-up was available on all surviving patients. Statistical analysis showed that in ordinary astrocytomas, each of the four histologic criteria, as well as the resultant grade, were strongly correlated to survival (P less than 0.0001). Median survival was 4 years in grade 2, 1.6 years in grade 3, and 0.7 years in grade 4 tumors. Of the two patients with grade 1 ordinary astrocytomas, 1 had 11 years of survival, and the other was alive at 15 years. Furthermore, based upon the Cox Model, grade was found to be the major prognostic factor, superceding the effects of age, sex, and location. Among ordinary astrocytomas, the grading system under consideration clearly distinguished four distinct grades of malignancy, whereas, the Kernohan grading system accurately distinguished only two major groups of patients. Survival curve of patients with our grade 2 tumors coincided with the grade 1 and 2 Kernohan survival curves. Similarly, our grade 4 survival curve coincided with the Kernohan grade 3 and 4 survival curves. As a result, our proposed grading method generated an individualized curve corresponding to grade 3 tumors. Double-blind grading between two independent observers was concordant in 94% of ordinary astrocytomas; reproducibility was 81% in low-grade (grades 1 and 2) and 96% in high-grade (grades 3 and 4) astrocytomas of ordinary type.(ABSTRACT TRUNCATED AT 400 WORDS)
— id: 33768, year: 1988, vol: 62, page: 2152, stat: Journal Article,

Computer-assisted stereotactic biopsy of intracranial lesions in pediatric patients
Davis DH; Kelly PJ; Marsh WR; Kall BA; Goerss SJ
1988 ;14(1):31-36, Pediatric neuroscience
A computer-assisted stereotactic biopsy technique has been used in 30 patient (ages 5 months to 16 years) with intracranial lesions (supratentorial in 23 and infratentorial in 7). The computer program integrates stereotactically gathered imaging data and permits preoperative planning of a biopsy trajectory. Diagnostic tissue was obtained in 27 cases. In 2 cases, therapeutic interventions--third ventriculostomy and cyst aspiration--were accomplished at the time of the biopsy. There were no major complications related to the procedure; however, 2 patients had transient neurologic deficits. Computer-assisted stereotactic biopsy is a valuable diagnostic procedure in the pediatric patient with an intracranial lesion
— id: 33705, year: 1988, vol: 14, page: 31, stat: Journal Article,

Cerebral astrocytomas: histopathologic correlation of MR and CT contrast enhancement with stereotactic biopsy
Earnest F 4th; Kelly PJ; Scheithauer BW; Kall BA; Cascino TL; Ehman RL; Forbes GS; Axley PL
1988 Mar;166(3):823-827, Radiology
Gadolinium-labeled diethylenetriaminepentaacetic acid was used as a contrast agent for stereotactic magnetic resonance (MR) imaging in six selected patients with brain tumors who underwent stereotactic biopsy. Regions of contrast enhancement demonstrated by computed tomography (CT) and MR imaging in four of the six patients correlated with areas of malignant neovascularity and endothelial proliferation within solid tumor. Radiation necrosis produced contrast enhancement indistinguishable from that of recurrent neoplasm. Isolated tumor cells within intact white matter were identified in biopsy specimens obtained outside of regions that were depicted as abnormal by contrast material-enhanced CT, as well as by precontrast and postcontrast T1- and T2-weighted MR images
— id: 33685, year: 1988, vol: 166, page: 823, stat: Journal Article,

Volumetric stereotactic surgical resection of intra-axial brain mass lesions
Kelly PJ
1988 Dec;63(12):1186-1198, Mayo Clinic proceedings
From August 1984 to August 1987 at the Mayo Clinic, 226 computer-assisted stereotactic resections based on computed tomography or magnetic resonance imaging (or both) were performed on 203 supratentorial and 23 infratentorial lesions in various deep-seated or essential brain locations. Histologic examination revealed 112 glial neoplasms, 70 nonglial tumors, and 44 nonneoplastic lesions. The overall morbidity was 9.3% (21 of 226 patients were worse after the procedure), and the 30-day operative mortality was 1% (2 patients). The procedure provides maximal cytoreduction in high-grade glial neoplasms but is most beneficial to patients who have histologically circumscribed tumors, such as pilocytic astrocytomas, metastatic neoplasms, and miscellaneous nonglial and nonneoplastic lesions
— id: 33766, year: 1988, vol: 63, page: 1186, stat: Journal Article,

Evolution of contemporary instrumentation for computer-assisted stereotactic surgery
Kelly PJ; Goerss SJ; Kall BA
1988 Sep;30(3):204-215, Surgical neurology
This article discusses the evolution of our stereotactic system which evolved from the commercially available Todd-Wells stereotactic instrument. The Todd-Wells frame was originally designed for radiographically based, functional neurosurgical procedures. We modified it for computed tomography compatibility and later devised localization systems for magnetic resonance imaging and digital angiography. Based on the limitations in the original design applying to our own set of requirements, including tumor stereotaxis, we totally redesigned the system around the arc-quadrant principle of the original Todd-Wells instrument. While this intermediate system was being used in our surgical practice, further limitations were noted and corrected in the system we presently use. The present stereotactic frame is completely interactive with an operating room computer system
— id: 33702, year: 1988, vol: 30, page: 204, stat: Journal Article,

The stereotaxic retractor in computer-assisted stereotaxic microsurgery. Technical note
Kelly PJ; Goerss SJ; Kall BA
1988 Aug;69(2):301-306, Journal of neurosurgery
The authors describe a cylindrical retractor that is attached to a standard stereotaxic frame. This retractor provides a route for stereotaxic procedures and exposure of and a reference structure for the computer-assisted removal of deep-seated intracranial lesions defined stereotaxically by computerized tomography and magnetic resonance imaging
— id: 33703, year: 1988, vol: 69, page: 301, stat: Journal Article,

Results of computed tomography-based computer-assisted stereotactic resection of metastatic intracranial tumors
Kelly PJ; Kall BA; Goerss SJ
1988 Jan;22(1 Pt 1):7-17, Neurosurgery
Forty-four patients underwent 45 computer-assisted stereotactic resections of intracranial metastases from various centrally located and deep-seated regions using methods described in this report and elsewhere. Gross total removal was achieved in all cases. There was no postoperative mortality (within 30 days). Postoperative neurological examinations revealed that: (a) of 26 who presented with preoperative neurological deficits, 13 were normal postoperatively, 7 were improved, 3 were unchanged, and 3 were worse; (b) 5 of 5 patients who had increased intracranial pressure preoperatively were normal postoperatively; and (c) 3 of 3 patients who had increased intracranial pressure and neurological deficit preoperatively were neurologically normal postoperatively. Nine of 10 patients who were neurologically normal preoperatively were normal postoperatively, and the other had transient upper extremity weakness after resection of a lesion in the contralateral motor strip. The 1-year survival in this group of patients was 62.5%. No local recurrence was noted in any patient. Computer-assisted stereotactic resection permits accurate localization of metastatic lesions and gross total resection from difficult locations with acceptable levels of morbidity
— id: 33704, year: 1988, vol: 22, page: 7, stat: Journal Article,

Cortical and cancellous bone: age-related changes in morphologic features, fluid spaces, and calcium homeostasis in dogs
Simonet WT; Bronk JT; Pinto MR; Williams EA; Meadows TH; Kelly PJ
1988 Feb;63(2):154-160, Mayo Clinic proceedings
The changes in cortical and cancellous bone that occur with aging were studied by measuring morphologic and physiologic variables for both types of bone in dogs. The percentage area of cortical and cancellous bone, rate of bone formation, vascular volume, bone water, and volume of distribution of calcium tracer all showed statistically significant changes at the time of bone maturity. Canine cortical bone cell volume progressively decreased with advancing age, and cancellous bone cell volume significantly decreased between adult and old dogs. The volume of distribution technique can be used to determine the relative contributions of cortical and cancellous bone to the total body exchangeable calcium ion pool
— id: 33767, year: 1988, vol: 63, page: 154, stat: Journal Article,

A histologic and cytologic method for the spatial definition of gliomas
Daumas-Duport C; Scheithauer BW; Kelly PJ
1987 Jun;62(6):435-449, Mayo Clinic proceedings
Because of the increasing application of stereotactic neurosurgical techniques not only in the diagnosis but also in the treatment of brain tumors, a demand for data regarding the spatial delimitation of gliomas is being created. Traditional histologic criteria were not established for detecting isolated tumor cells located at the boundaries of gliomas. Standard histologic techniques used for processing surgical specimens result in preparations of insufficient quality to allow the detection of minimal tumor infiltrates within normal brain parenchyma. Consequently, histologic examination has been considered an unreliable method of determining the boundaries of gliomas. In this study, we describe in detail an improved technique of biopsy specimen preparation that involves the use of glutaraldehyde-fixed and hemalum-phloxine-stained paraffin sections as well as alcohol-fixed and hemalum-phloxine-stained smears. In concert, these methods allow visualization of delicate cytologic details and are complementary in assessing the presence of isolated tumor cells at the periphery of gliomas. We define morphologic criteria for the accurate identification of isolated neoplastic cells and for their distinction from normal or reactive glial elements. These morphologic criteria include classic cytologic features of malignant lesions (such as nuclear pleomorphism and hyperchromasia) as well as the assessment of tumor architecture and cellular spatial relationships
— id: 33689, year: 1987, vol: 62, page: 435, stat: Journal Article,

Computer-assisted stereotactic biopsy of intracranial lesions
Davis DH; Kelly PJ; Marsh WR; Kall BA; Goerss SJ
1987 ;50(1-6):172-177, Applied neurophysiology
The use of a computer program that allows the integration of stereotactically gathered CT, MRI and digital angiographic data in the planning of a biopsy trajectory is described. This system has been used to perform 447 stereotactic biopsies in 439 patients. Intracranial hemorrhages occurred in three patients; combined morbidity and mortality was less than 1%. Incorporation of angiographic data and visualization of the surgical trajectory enhances the safety and accuracy of stereotactic biopsy of intracranial lesions
— id: 33708, year: 1987, vol: 50, page: 172, stat: Journal Article,

Automated stereotactic positioning system
Goerss SJ; Kelly PJ; Kall BA
1987 ;50(1-6):100-106, Applied neurophysiology
An automated stereotactic machine has been interfaced to a surgical computer to complete a totally interactive surgical system capable of locating tumor volumes. Stepper motors, activated by the host computer, drive a three-dimensional slide to position the patient's head with respect to a fixed arc, locating the surgical target. Linear encoders on each axis create a closed-loop positioning system and a digital display for visual inspection of the slide's position. The 160-mm arc directs all instrumentation to its isocenter, regardless of the two angular settings, providing maximum freedom in selecting a safe trajectory to the target. Phantom test points compatible with computerized tomographic and magnetic resonance imaging were repeatedly scanned to determine the overall system accuracy, which approached 0.6 mm, depending on the spatial resolution of the image. This stereotactic device may be used to perform stereotactic laser craniotomies, biopsies, 192Ir implants for interstitial radiation, third ventriculostomies and functional procedures
— id: 33710, year: 1987, vol: 50, page: 100, stat: Journal Article,

Computer assisted stereotactic placement of Ommaya reservoirs for delivery of chemotherapeutic agents in cancer patients
Hagen NA; O'Neill BP; Kelly PJ
1987 ;5(3):273-276, Journal of neuro-oncology
A new technique of Ommaya reservoir placement using computer assisted reconstruction of CT data bases is described. This technique permits stereotactic placement of ventricular catheters in small or normal sized ventricles. It should be particularly useful in patients where the conventional technique is not applicable
— id: 33734, year: 1987, vol: 5, page: 273, stat: Journal Article,

Future possibilities in stereotactic surgery: where are we going?
Kelly PJ
1987 ;50(1-6):1-8, Applied neurophysiology
— id: 33765, year: 1987, vol: 50, page: 1, stat: Journal Article,

Computer-assisted stereotactic ventralis lateralis thalamotomy with microelectrode recording control in patients with Parkinson's disease
Kelly PJ; Ahlskog JE; Goerss SJ; Daube JR; Duffy JR; Kall BA
1987 Aug;62(8):655-664, Mayo Clinic proceedings
Stereotactic ventralis lateralis thalamotomy can be performed in selected patients with medically intractable parkinsonian tremor and rigidity. New technology, including computed tomography-based stereotaxis and microelectrode recording techniques, provides a data base for precise localization of thalamic lesions tailored to each patient and thus reduces the risk associated with such a procedure. At our institution, 12 patients with medically intractable parkinsonian tremor have undergone this procedure; all experienced alleviation or cessation of the tremor and no permanent disabling neurologic sequelae
— id: 33706, year: 1987, vol: 62, page: 655, stat: Journal Article,

Imaging-based stereotaxic serial biopsies in untreated intracranial glial neoplasms
Kelly PJ; Daumas-Duport C; Kispert DB; Kall BA; Scheithauer BW; Illig JJ
1987 Jun;66(6):865-874, Journal of neurosurgery
Forty patients with previously untreated intracranial glial neoplasms underwent stereotaxic serial biopsies assisted by computerized tomography (CT) and magnetic resonance imaging (MRI). Tumor volumes defined by computer reconstruction of contrast enhancement and low-attenuation boundaries on CT and T1 and T2 prolongation on MRI revealed that tumor volumes defined by T2-weighted MRI scans were larger than those defined by low-attenuation or contrast enhancement on CT scans. Histological analysis of 195 biopsy specimens obtained from various locations within the volumes defined by CT and MRI revealed that: contrast enhancement most often corresponded to tumor tissue without intervening parenchyma; hypodensity corresponded to parenchyma infiltrated by isolated tumor cells or in some instances to tumor tissue in low-grade gliomas or to simple edema; and isolated tumor cell infiltration extended at least as far as T2 prolongation on magnetic resonance images. This information may be useful in planning surgical procedures and radiation therapy in patients with intracranial glial neoplasms
— id: 33688, year: 1987, vol: 66, page: 865, stat: Journal Article,

Stereotactic histologic correlations of computed tomography- and magnetic resonance imaging-defined abnormalities in patients with glial neoplasms
Kelly PJ; Daumas-Duport C; Scheithauer BW; Kall BA; Kispert DB
1987 Jun;62(6):450-459, Mayo Clinic proceedings
In 39 patients who harbored previously untreated astrocytomas (21 patients), oligoastrocytomas (9 patients), or oligodendrogliomas (9 patients), computed tomographic (CT) and magnetic resonance imaging (MRI) findings were correlated with stereotactic serial biopsy findings. The 39 patients were classified as having one of three types of tumor: type I (1 patient), which consisted only of circumscribed tumor tissue; type II (26 patients), which consisted of tumor tissue and isolated tumor cells; or type III (11 patients), which consisted of intact parenchyma infiltrated by isolated tumor cells. (In one patient, the biopsy sampling was inadequate for determining the type of tumor.) In high-grade lesions, tumor tissue was obtained from CT contrast-enhancing regions, and the area of enhancement accurately defined the tumor tissue volume. In low-grade lesions, tumor tissue was hypodense and indistinguishable from parenchyma infiltrated by isolated tumor cells on both CT and MRI. Isolated tumor cells usually extended as far as the prolongation of T2 on T2-weighted MRI of high-grade and low-grade tumors. CT and MRI detection of boundaries and stereotactic serial biopsies are necessary for the demarcation of glial neoplasms into tumor tissue and isolated tumor cell volumes as well as for the determination of the spatial extent of each component. This information is important for determining appropriate treatment
— id: 33687, year: 1987, vol: 62, page: 450, stat: Journal Article,

Computer-interactive stereotactic resection of deep-seated and centrally located intraaxial brain lesions
Kelly PJ; Kall BA; Goerss SJ
1987 ;50(1-6):107-113, Applied neurophysiology
The carbon dioxide laser has been incorporated into a computer-interactive stereotactic system for precision resection of deep-seated intraaxial neoplasma defined by stereotactic computed tomography and magnetic resonance imaging. One hundred and ninety-seven procedures were performed on 191 patients having deep-seated lesions. Postoperative results have been satisfactory as regards the postoperative condition of the patient in consideration of the completeness of tumor removal achieved
— id: 33709, year: 1987, vol: 50, page: 107, stat: Journal Article,

Magnetic resonance imaging-based computer-assisted stereotactic resection of the hippocampus and amygdala in patients with temporal lobe epilepsy
Kelly PJ; Sharbrough FW; Kall BA; Goerss SJ
1987 Feb;62(2):103-108, Mayo Clinic proceedings
In patients with medically intractable complex partial seizures of temporal lobe origin, stereotactic amygdalohippocampectomy can now provide excellent results. Target structures can be accurately identified and completely resected with use of a carbon dioxide laser. In a series of 18 patients who underwent this computer-interactive procedure, all experienced a cessation or dramatic reduction in frequency of seizure activity. Because the inferior optic radiations are disrupted with use of the posterolateral approach, nondisabling postoperative visual field deficits always ensue. In addition, two of our patients who underwent left-sided procedures had transient minor speech problems, perhaps attributable to postoperative swelling of the lateral temporal lobe. Patients in whom a surface electroencephalogram discloses a posterior temporal focus of seizure activity are candidates for stereotactic amygdalohippocampectomy
— id: 33707, year: 1987, vol: 62, page: 103, stat: Journal Article,

Sedation for stereotactic headframe application: a randomized comparison of two techniques
Lanier WL; Hool GJ; Faust RJ; Cucchiara RF; Kelly PJ
1987 ;50(1-6):227-232, Applied neurophysiology
A prospective, randomized study was performed in 87 patients to compare the safety, efficacy and dose requirements of two sedation techniques for stereotactic headframe application. Sedation administration and headframe application averaged 30 min. Fifty patients weighing 76 +/- 13 kg (mean +/- SD) received mean doses of 154 micrograms fentanyl plus 5.5 mg droperidol i.v. (FD group). An additional 37 patients weighing 76 +/- 19 kg received mean doses of 127 micrograms fentanyl plus 6.7 mg Valium (diazepam; FV group). Both treatments provided excellent hemodynamic stability and a low incidence of adverse side effects while providing adequate analgesia and sedation. The incidence of anesthetist-assessed patient anxiety and discomfort was more favorable in the FD group
— id: 33735, year: 1987, vol: 50, page: 227, stat: Journal Article,

Stereotactic resection of juvenile pilocytic astrocytomas of the thalamus and basal ganglia
McGirr SJ; Kelly PJ; Scheithauer BW
1987 Mar;20(3):447-452, Neurosurgery
Six patients with juvenile pilocytic astrocytomas of the thalamus or basal ganglia underwent seven computer-assisted stereotactic laser craniotomies with complete or nearly complete removal of the tumor in all cases. The tumor was located in the right basal ganglia in one patient, the left basal ganglia in one patient, and the left thalamus in four patients. Postoperative assessment of the completeness of tumor removal was confirmed by contrast-enhanced computed tomographic scanning within the first 2 weeks after operation. None of the patients was neurologically worse after the procedure, and five were improved. The duration of follow-up ranged from 6 months to 3.5 years. In this group of patients, the computer-assisted, stereotactically guided resection of these deeply located, benign tumors was accomplished with no morbidity or mortality
— id: 33690, year: 1987, vol: 20, page: 447, stat: Journal Article,

Computer-assisted stereotaxic biopsy for the diagnosis of primary central nervous system lymphoma
O'Neill BP; Kelly PJ; Earle JD; Scheithauer B; Banks PM
1987 Jul;37(7):1160-1164, Neurology
Primary CNS lymphoma was diagnosed in 13 patients after stereotaxic biopsy of indeterminate intracerebral mass lesions. Two patients also had laser extirpation of CT-visible tumor. The group consisted of 10 men and 3 women, aged 17 to 81 (mean, 55 years; median, 60 years). The lesions on CT were characteristically hyperdense, homogeneously contrast-enhancing, and associated with mild to moderate mass effect. Five patients had more than one lesion visible on CT. Complete staging procedures for occult systemic lymphoma were negative in all 13 patients. The majority (eight) of the tumors were of the diffuse, large-cell type. Five biopsy specimens underwent special immunostaining as a supplemental diagnostic effort. Two patients with small lymphocytic tumors demonstrated features consistent with T cell phenotype. Two patients with diffuse, large-cell tumors were confirmed as B cell phenotype by monotypic immunoglobulin light chain content. Primary CNS lymphomas represent a treatable group of primary brain tumors. Because of their tendency to develop in deep cerebral regions, they are often inaccessible to conventional neurosurgical techniques. We propose that stereotaxic neurosurgery can provide safe and accurate diagnosis, which is a prelude to planning comprehensive management
— id: 33686, year: 1987, vol: 37, page: 1160, stat: Journal Article,

CT computerised stereotactic biopsy for low density CT lesions presenting with epilepsy
Wilden JN; Kelly PJ
1987 Oct;50(10):1302-1305, Journal of neurology neurosurgery & psychiatry
Thirty five patients presenting with epilepsy alone and non-enhancing low-density lesion on the CT scan underwent a computer-assisted CT-guided stereotactic biopsy with stereotactic angiographic control. There was no mortality or morbidity in this series and the diagnostic yield was 97%. Thirty four patients had low grade intra-axial neoplasms. After an estimation of the pathological extent of the tumour, three patients underwent a computer-assisted stereotactic laser resection and 28 patients had radiotherapy
— id: 33733, year: 1987, vol: 50, page: 1302, stat: Journal Article,

The computer as a stereotactic surgical instrument
Kall BA; Kelly PJ; Goerss SJ
1986 Dec;8(4):201-208, Neurological research
We have developed methodology and stereotactic software for an operating room computer and imaging system. Patients undergo preoperative CT, MR and DSA imaging with their heads fixed in a stereotactic headholder. Localization systems attach to the headholder during the studies to create reference marks for computer transformation of points and volumes into three-dimensional stereotactic space. At the operating room computer console, the surgeon selects target points, avascular trajectories and tumour boundaries for volume reconstruction. Surgical approaches are simulated and target coordinates calculated. During surgery, the computer interactively monitors the position of stereotactically directed surgical instruments in relationship to the resident database along any viewing angle and conveniently superimposes the multiple data sources. We have found this system useful to provide rapid data acquisition and retrieval, accurate target point calculations, lesion volume reconstructions, and a convenient ability to reformat data from multiple sources in a manner useful to the surgeon and beneficial to the patient
— id: 33711, year: 1986, vol: 8, page: 201, stat: Journal Article,

Applications and methodology for contemporary stereotactic surgery
Kelly PJ
1986 Mar;8(1):2-12, Neurological research
Stereotactic surgery was first described for functional exploration of animal brains in 1908. It has been used in human neurosurgery for almost forty years, primarily for the accurate placement of subcortical probes for the production of therapeutic lesions in the treatment of movement disorders and pain. After the introduction of L-Dopa in 1968, enthusiasm diminished for the technique. In the past ten years, primarily due to the development of new imaging technologies, stereotaxis has enjoyed a renaissance as new applications have been described. Stereotactic surgery may be utilized for neuro-ablative and neuro-augmentative procedures. It can also be useful in the diagnosis of brain tumours by stereotactic biopsy and for treatment of subcortical neoplasms by interstitial irradiation or computer-assisted stereotactic laser resection. With the development of computer technology, many new procedures, refinements of old procedures, and development of new applications are possible
— id: 33762, year: 1986, vol: 8, page: 2, stat: Journal Article,

Computer-assisted stereotaxis: new approaches for the management of intracranial intra-axial tumors
Kelly PJ
1986 Apr;36(4):535-541, Neurology
Modifications of traditional stereotactic procedures have provided new options for the diagnosis and treatment of intracranial intra-axial neoplasms. The development of specific computer software for the incorporation of CT, MRI, and digital angiography data bases into a stereotactically defined computer image matrix for treatment planning and for interactive surgery allows a precision never before possible. These tumors may be stereotactically biopsied and treated by the stereotactic implantation of radionuclide sources or resected using computer-assisted stereotactic laser microsurgical techniques
— id: 33764, year: 1986, vol: 36, page: 535, stat: Journal Article,

Computed tomography-based stereotactic third ventriculostomy: technical note
Kelly PJ; Goerss S; Kall BA; Kispert DB
1986 Jun;18(6):791-794, Neurosurgery
This report describes a computed tomography-based computer-assisted stereotactic technique for performing 3rd ventriculostomy. The procedure has been performed on seven patients with acquired obstructive hydrocephalus of various etiologies. None of these patients have yet required shunting
— id: 33712, year: 1986, vol: 18, page: 791, stat: Journal Article,

Results of computer-assisted stereotactic laser resection of deep-seated intracranial lesions
Kelly PJ; Kall BA; Goerss S; Cascino TL
1986 Jan;61(1):20-27, Mayo Clinic proceedings
A computer-assisted stereotactic system has been developed for the precise resection of deep-seated intracranial neoplasms. After the tumor volume is reconstructed from computed tomographic and magnetic resonance imaging data, a computer-monitored, stereotactically directed carbon dioxide laser is used to vaporize the intracranial tumor. A computer graphics terminal is used to monitor the position of the laser in relationship to the planar slices through the tumor, which are reformatted orthogonally to the surgical plane of view. This procedure produced satisfactory postoperative neurologic results in 36 of the 41 patients who underwent treatment. The system provides precise surgical control in three-dimensional space for the safe resection of substantial amounts (as assessed by postoperative computed tomography) of intra-axial neoplasms
— id: 33714, year: 1986, vol: 61, page: 20, stat: Journal Article,

Computer-assisted stereotaxic laser resection of intra-axial brain neoplasms
Kelly PJ; Kall BA; Goerss S; Earnest F 4th
1986 Mar;64(3):427-439, Journal of neurosurgery
Computer interpolation of stereotaxic computerized tomography (CT) scanning data allows the transposition of a tumor volume in stereotaxic space. A stereotaxically directed and computer-monitored CO2 laser is then utilized to vaporize that volume as the surgeon monitors the position of a cursor representing the laser beam against planar contours of the tumor displayed on an operating room computer monitor. Computer-assisted stereotaxic laser microsurgery provides precise three-dimensional control for aggressive resection of deep-seated tumors from neurologically important areas with acceptable postoperative results. Thus, a significant cytoreduction can be achieved in addition to providing a tissue diagnosis and internal decompression. The authors report 83 computer-assisted stereotaxic laser procedures for tumor excision in 78 patients. The tumors were located in the thalamus/basal ganglia in 15 patients, ventricular system in five, corpus callosum in four, brain stem in three, and deep and centrally in the hemispheres in 51. Histologically, there were 26 glioblastomas, seven grade III astrocytomas, 14 grade II astrocytomas, 14 metastatic tumors, nine vascular lesions, and eight miscellaneous lesions. Resection of these subcortical lesions was confirmed by postoperative contrast-enhanced CT scanning. Neurological examinations performed 1 week after the 83 procedures revealed that 48 patients had improved from their preoperative level and 23 were unchanged (12 were neurologically normal preoperatively). Twelve patients had an increase in a preoperative neurological deficit, three of whom died in the postoperative period: one from infection, one from pulmonary emboli, and one from brain-stem edema. The average survival period (37.6 weeks) of patients having glioblastomas treated by this technique and irradiation was no different from that of patients having glioblastomas in more favorable locations treated by conventional surgery and irradiation. Patients with circumscribed lower-grade astrocytomas did better in terms of morbidity and completeness of resection than those with infiltrative neoplasms. Other circumscribed lesions, such as metastatic tumors, vascular lesions, and intraventricular tumors, were easily resected by the technique described
— id: 33713, year: 1986, vol: 64, page: 427, stat: Journal Article,

Application of ultrasound imaging to stereotactic brain tumor surgery
Koivukangas J; Kelly PJ
1986 ;18 Suppl 47(3):25-32, Annals of clinical research
This report describes the first application of intraoperative ultrasound to the stereotactic removal of subcortical brain tumors, here specifically applied to the Kelly system for stereotactic computer-controlled laser resection. The feasibility of ultrasound control of such procedures was demonstrated in the two cases of resection of cerebral astrocytoma presented in this paper. The chief benefits of ultrasound imaging seem to be the supplementary data it gives on the tumor itself, and the possibility of real-time imaging to follow the effects of tumor removal at successive stages of the procedure
— id: 33736, year: 1986, vol: 18 Suppl 47, page: 25, stat: Journal Article,

Clip-grafts in microvascular decompression of the posterior fossa. Technical note
Laws ER Jr; Kelly PJ; Sundt TM Jr
1986 Apr;64(4):679-681, Journal of neurosurgery
A method is described for the protection of the trigeminal root from recurrent vascular irritation or compression after posterior fossa microvascular decompression. A vascular clip-graft, using a Sundt clip of suitable size, is applied to the sensory root of the trigeminal nerve. The technique has proven safe and effective in a series of nine patients followed for up to 28 months
— id: 33737, year: 1986, vol: 64, page: 679, stat: Journal Article,

The role of intracranial surgery for the treatment of malignant gliomas
Ransohoff J; Kelly P; Laws E
1986 Mar;13(1):27-37, Seminars in oncology
— id: 33763, year: 1986, vol: 13, page: 27, stat: Journal Article,

Methodology and clinical experience with computed tomography and a computer-resident stereotactic atlas
Kall BA; Kelly PJ; Goerss S; Frieder G
1985 Sep;17(3):400-407, Neurosurgery
We have developed a computer-resident stereotactic atlas of the human brain that quantitatively defines subcortical structures within anatomical landmarks detected on obliquely reconstructed computed tomography (CT) slices. Horizontal stereotactic atlas sections can be stretched and contracted by polar transformation and labeled by a computer to fit within these CT scan-defined landmarks. The stereotactic coordinates of any substructure on the atlas-labeled CT slice may then be calculated by the computer and expressed in mechanical adjustments on a stereotactic surgical frame located in the operating room. We demonstrate the use of this method in the stereotactic treatment of movement disorders as an augmentation to conventional ventriculography and microelectrode recording
— id: 33715, year: 1985, vol: 17, page: 400, stat: Journal Article,

Interactive stereotactic surgical system for the removal of intracranial tumors utilizing the CO2 laser and CT-derived database
Kall BA; Kelly PJ; Goerss SJ
1985 Feb;32(2):112-116, IEEE transactions on biomedical engineering
— id: 33716, year: 1985, vol: 32, page: 112, stat: Journal Article,

Surgical options for patients with deep-seated brain tumors: computer-assisted stereotactic biopsy
Kelly PJ; Earnest F 4th; Kall BA; Goerss SJ; Scheithauer B
1985 Apr;60(4):223-229, Mayo Clinic proceedings
The histologic nature of deep-seated intracranial lesions can be determined by using a computer-assisted stereotactic biopsy technique. The procedures are performed with use of local anesthesia. A data base consisting of stereotactic computed tomographic scans and stereotactic cerebral angiography is acquired. Target coordinates and trajectory approach angles are calculated by using a computer system in the operating room. Since July 1984, 36 patients with a variety of pathologic lesions in various intracranial sites have undergone this procedure at our institution. Of the 36 patients thought to have neoplastic lesions preoperatively, 6 were found to have nonneoplastic lesions, information that was of importance in the therapeutic management of these patients. Of the 30 patients with tumors, 24 had astrocytomas of various grades, 3 had metastatic lesions, and an additional 3 had lymphomas. Computer-assisted stereotactic biopsy with arteriographic control is an accurate and relatively safe method of determining the histologic nature of any suspicious intracranial lesion
— id: 33691, year: 1985, vol: 60, page: 223, stat: Journal Article,

Present and future developments of stereotactic technology
Kelly PJ; Kall BA; Goerss S; Earnest F
1985 ;48(1-6):1-6, Applied neurophysiology
Incorporation of a surgical computer system into stereotactic methodology provides the facility for efficient utilization of the multiple data bases at the disposal of the modern stereotactician. Computed tomography, magnetic resonance imaging, and digital fluoroscopy data gathered in stereotactic conditions are digitized into a stereotactic surgical matrix for surgical planning and interactive surgical procedures. The advantages of this system are illustrated in stereotactic biopsy, interstitial irradiation, and laser resections of intracranial tumors
— id: 33717, year: 1985, vol: 48, page: 1, stat: Journal Article,

An overview of CT based stereotactic systems for the localization of intracranial lesions
Alker G; Kelly PJ
1984 Jul-Aug;8(4):193-196, Computerized radiology
Computed tomography, with its inherent accuracy in identifying and localizing intracranial lesions, has been adapted by several groups for use in stereotactic neurosurgical procedures. The systems range from the use of data obtained on conventional CT scans to installation of a dedicated CT scanner in the operating room equipped for stereotactic surgery. Although the GE-8800 scanner is used most frequently, others are also suitable. Adaptations of standard commercially available stereotactic frames are used by some groups while others designed frames specifically for this purpose. The paper is an overview of systems described in the literature to date
— id: 33739, year: 1984, vol: 8, page: 193, stat: Journal Article,

Symposium on musculoskeletal sepsis
Fitzgerald, Robert H.; Kelly, Patrick J
Philadelphia : Saunders, 1984,
— id: 27, year: 1984, vol: , page: , stat: ,

Method of computed tomography-based stereotactic biopsy with arteriographic control
Kelly PJ; Alker GJ Jr; Kall BA; Goerss S
1984 Feb;14(2):172-177, Neurosurgery
A method for computed tomography (CT)-based stereotactic biopsy of intracranial neoplasms with arteriographic control is described. Stereotactic CT and digitized stereotactic arteriographic data are input to a three-dimensional computer matrix that corresponds to the coordinate system of a stereotactic frame located in the operating room. A site for biopsy is selected by cursor from the CT display screen. The computer calculates and outputs the mechanical adjustments of the stereotactic frame necessary to place the target point into the focal point of the frame. Horizontal and vertical approach angles are determined from the digitized arteriogram and are displayed as settings on the stereotactic frame that represent an avascular trajectory along which the lesion may be biopsied safely. This procedure has been used successfully in 86 patients, with no morbidity or mortality
— id: 33720, year: 1984, vol: 14, page: 172, stat: Journal Article,

Computer simulation for the stereotactic placement of interstitial radionuclide sources into computed tomography-defined tumor volumes
Kelly PJ; Kall BA; Goerss S
1984 Apr;14(4):442-448, Neurosurgery
This report describes a method for the preoperative determination of radioactive interstitial source placement within computed tomography (CT)-defined tumor boundaries. The method utilizes CT data obtained under stereotactic conditions. Tumor boundaries are digitized from CT slices and are retained in a three-dimensional computer matrix. A solid tumor volume is created by an interpolation program and may be sliced orthogonal to any specific stereotactic surgical view line. The surgeon may simulate radioactive source placement within the slices and view the resultant isodose configuration against tumor contours on successive slices. Once the best source placement has been determined, the computer outputs the mechanical adjustments that will be necessary on a stereotactic frame located in the operating room for the stereotactic placement of each source and gives the length of each source. Sources are stereotactically implanted utilizing a double-catheter afterloading technique
— id: 33719, year: 1984, vol: 14, page: 442, stat: Journal Article,

Transposition of volumetric information derived from computed tomography scanning into stereotactic space
Kelly PJ; Kall BA; Goerss S
1984 May;21(5):465-471, Surgical neurology
A method for translation of a tumor volume defined by computed tomography (CT) into stereotactic space using a CT-comparible stereotactic headholder, localizing system, arc--quadrant stereotactic instrument, and operating room computer system is described. Clinical applications, including computer-assisted stereotactic laser resection of deep-seated neoplasms of the central nervous system and simulation of stereotactically implanted radionuclide sources, are discussed
— id: 33718, year: 1984, vol: 21, page: 465, stat: Journal Article,

Stereotaxic laser ablation of intracranial lesions
Alker G; Kelly PJ; Kall B; Goerss S
1983 May-Jun;4(3):727-730, AJNR. American journal of neuroradiology
A technique is described which combines computed tomography-based stereotaxic localization and CO2 laser ablation of certain intracranial lesions with a high degree of accuracy. In 24 patients operated on with this technique, total ablation of the lesion was achieved in 19 and incomplete ablation in the other five. Though not perfect, this method is a new approach to intracranial lesions that promises to be more efficacious as future developments occur
— id: 33721, year: 1983, vol: 4, page: 727, stat: Journal Article,

Future possibilities in stereotactic neurosurgery
Kelly PJ
1983 Jan;19(1):4-9, Surgical neurology
— id: 33761, year: 1983, vol: 19, page: 4, stat: Journal Article,

Stereotactic CT scanning for the biopsy of intracranial lesions and functional neurosurgery
Kelly PJ; Kall B; Goerss S
1983 ;46(1-4):193-199, Applied neurophysiology
This report describes a system for incorporation of stereotactic CT scanning data, stereotactic arteriographic data and a computer-generated stereotactic atlas into a three-dimensional matrix utilizing an operating room computer. 86 patients have undergone computer-assisted stereotactic biopsies of intracranial lesions without mortality or neurologic morbidity. Neuroablative and neuroaugmentative procedures have been performed on 5 patients using the CT stereotactic atlas with good correlation with target points determined by ventriculography and microelectrode recording
— id: 33722, year: 1983, vol: 46, page: 193, stat: Journal Article,

Precision resection of intra-axial CNS lesions by CT-based stereotactic craniotomy and computer monitored CO2 laser
Kelly PJ; Kall B; Goerss S; Alker GJ Jr
1983 ;68(1-2):1-9, Acta neurochirurgica
This report describes an open stereotactic technique by which a tumour volume reconstructed in stereotactic space from CT data is removed by stereotactic CO2 laser vaporization. The position of the laser beam in relation to the tumour outlines is monitored by computer and displayed to the surgeon on a graphics display terminal in the operating room. Twenty-six (26) of these procedures have been performed on twenty-four (24) patients with deep-seated intra-axial neoplasms (23) and arteriovenous malformation (1). Post-operative CT scanning revealed no evidence of contrast enhancing lesions in nineteen (19) patients while a small amount of residual tumour was noted in five (5) patients post-operatively. This method has proven itself valuable for maintaining three-dimensional surgical orientation for the resection of intra-axial neoplasms from neurologically important areas
— id: 33723, year: 1983, vol: 68, page: 1, stat: Journal Article,

A computed tomographic stereotactic adaptation system
Goerss S; Kelly PJ; Kall B; Alker GJ Jr
1982 Mar;10(3):375-379, Neurosurgery
An adaptation to render an existing popular stereotactic apparatus compatible with computed tomography (CT) is described. A localization system attaches to the stereotactic head holder and a simple computer program allows considerable accuracy in the translation of CT data into stereotactic space in the operating room
— id: 33724, year: 1982, vol: 10, page: 375, stat: Journal Article,

Computer-assisted stereotactic microsurgery for the treatment of intracranial neoplasms
Kelly PJ; Alker GJ Jr; Goerss S
1982 Mar;10(3):324-331, Neurosurgery
This paper describes a stereotactic CO2 laser system for the removal of intra-axial, intracranial neoplasms. The volume of the neoplasm is transferred into stereotactic space by computer reconstruction of data derived by computed tomography (CT) performed under stereotactic conditions. The tumor volume is sliced in a plane orthogonal to the surgical approach, and slices at specific distances from the focal point of the stereotactic frame are displayed on a graphics monitor in the operating suite along with a cursor representing the position of the surgical laser. Laser vaporization of sequential slices of the tumor results in a cavity, the formation of which is monitored by anteroposterior and lateral roentgenograms. Fifteen stereotactic laser procedures have been performed on 13 patients, and the results are discussed. By this method, it is theoretically possible to remove all of an intracranial neoplasm detected by CT scanning
— id: 33732, year: 1982, vol: 10, page: 324, stat: Journal Article,

A stereotactic approach to deep-seated central nervous system neoplasms using the carbon dioxide laser
Kelly PJ; Alker GJ Jr
1981 May;15(5):331-334, Surgical neurology
This report describes a technique in which deep-seated CNS neoplasms, the volume and shape of which had been determined and stereotactically localized by computer reconstruction of CT data, were vaporized with a carbon dioxide laser attached to a stereotactic frame. The clinical results with 6 patients treated by this technique are presented
— id: 33738, year: 1981, vol: 15, page: 331, stat: Journal Article,

A study on the tridimensional distribution of somatosensory evoked responses in human thalamus to aid the placement of stimulating electrodes for treatment of pain
Giorgi C; Kelly PJ; Eaton DC; Guiot G; Derome P
1980 ;30(3):279-287, Acta neurochirurgica. Supplementum
— id: 33743, year: 1980, vol: 30, page: 279, stat: Journal Article,

Microelectrode recording for the somatotopic placement of stereotactic thalamic lesions in the treatment of parkinsonian and cerebellar intention tremor
Kelly PJ
1980 ;43(3-5):262-266, Applied neurophysiology
Patients with parkinsonian tremor and rigidity and cerebellar intention tremor can be effectively treated with thalamic lesions provided that an accurate neurophysiologic method is employed to compensate for individual spatial variability of subcortical structures. The method described employs a technique of microelectrode recording in which the homuncular organization in ventralis posterior is explored and gives information as to the ideal laterality of lateral thalamic nuclear mass lesions for the treatment of tremor. This procedure has been used in 11 patients, 9 with Parkinson's disease and 2 with cerebellar intention tremor with good results and no complications to date
— id: 33760, year: 1980, vol: 43, page: 262, stat: Journal Article,

A method for stereotactic laser microsurgery in the treatment of deep-seated CNS neoplasms
Kelly PJ; Alker GJ Jr
1980 ;43(3-5):210-215, Applied neurophysiology
Intracranial tumors are reconstructed in stereotactic space by means of computerized axial tomographic data. The intracranial tumor is operated on with the patient in the stereotactic frame using a carbon dioxide laser to approach the lesion and vaporize it. Ultimately, a gas-filled cavity results which can be monitored on AP and lateral radiographs. Vaporization continues until the cavity produced is superimposable on the coronal and sagittal CT reconstruction. 2 cases treated by this method are presented
— id: 33740, year: 1980, vol: 43, page: 210, stat: Journal Article,

The long-term results of stereotaxic surgery and L-dopa therapy in patients with Parkinson's disease. A 10-year follow-up study
Kelly PJ; Gillingham FJ
1980 Sep;53(3):332-337, Journal of neurosurgery
Sixty patients with Parkinson's disease underwent sterotaxic surgery in Edinburgh between 1965 and 1967, and were examined every 2 years for a total follow-up period of 10 years. Although stereotaxic surgery had been extremely effective in treating tremor and rigidity, the other manifestations of Parkinson's disease were noted to progressively affect more patients at each follow-up examination. L-dopa therapy was instituted in 36 patients after 1968. The effect of L-dopa on bradykinesia was remarkable, but the long-term benefit on the other manifestations of Parkinson's disease was negligible. Furthermore in most cases L-dopa became progressively ineffective for bradykinesia after 3 to 5 years. L-dopa-induced tremor and involuntary movements were less frequently noted in limbs contralateral to the side of a previous stereotaxic procedure. It was concluded that in patients presenting with tremor and rigidity as the major problem in their parkinsonian syndrome, the most effective form of palliative therapy is stereotaxic surgery, and that L-dopa should be reserved for the management of bradykinesia
— id: 33742, year: 1980, vol: 53, page: 332, stat: Journal Article,

Symptomatic cerebral histoplasmoma. Case report
Schochet SS Jr; Sarwar M; Kelly PJ; Masel BE
1980 Feb;52(2):273-275, Journal of neurosurgery
A 53-year-old man, with a past history of a thoracotomy 7 years previously, developed seizures. A computerized tomography scan with contrast medium revealed a peripheral ring-like lesion in the anterolateral part of the right parietal lobe. Pathological evaluation of the resected lesion demonstrated it to be a histoplasmoma. Although rare, a histoplasmoma should be included in the differential diagnosis of a ring-shaped lesion in a patient with previous pulmonary disease
— id: 33752, year: 1980, vol: 52, page: 273, stat: Journal Article,

Intracranial introduction of a nasogastric tube in a patient with a pituitary tumor
Guerra B; Slade TL; Kelly PJ
1979 Aug;12(2):135-136, Surgical neurology
This case report describes the complication of intracranial introduction of a nasogastric tube in a patient with a pituitary adenoma
— id: 33746, year: 1979, vol: 12, page: 135, stat: Journal Article,

Radionuclide cerebral angiography and the timing of aneurysm surgery
Kelly PJ; Gorten RJ; Rose JE; Grossman RG; Eisenberg HM
1979 Aug;5(2):202-207, Neurosurgery
Forty-five patients with subarachnoid hemorrhage due to verified intracranial aneurysms were studied prospectively to determine whether delaying operations in those patients with abnormal cerebral perfusion, assessed by radionuclide dynamic scanning, would lower case management mortality. Twenty-nine patients had intracranial operations when their radionuclide dynamic scans demonstrated normal perfusion. The one death in this group occurred in a patient who suffered a massive hemorrhage during operation as the bone flap was elevated. There were no instances of delayed spasm after operation. Of the 16 remaining patients who were treated without operation, 5 died. Only 1 of these deaths resulted from recurrent hemorrhage. This patient had normal cerebral perfusion but was not operated upon because of severe associated medical problems. Cerebral infarction occurred in 10 of the 16 unoperated patients, all of whom had persistently decreased cerebral perfusion. Four of these patients died of their infarctions or related causes. Although a trend related vessel caliber as seen on arteriograms and perfusion delay seen on dynamic scanning, individual exceptions were numerous. This study shows that radionuclide scanning, a safe procedure, is useful for identifying two types of patients: those with normal perfusion prone to rebleeding in whom an early operation is safe and those in whom perfusion is decreased. The latter group is prone to cerebral infarction, but rebleeding from the aneurysm is unlikely. Operation should be delayed in these patients until cerebral perfusion returns to normal or for several weeks if cerebral perfusion remains diminished
— id: 33741, year: 1979, vol: 5, page: 202, stat: Journal Article,

Thalamic spatial variability and the surgical results of lesions placed with neurophysiologic control
Kelly PJ; Derome P; Guiot G
1978 May;9(5):307-315, Surgical neurology
One hundred stereotactic thalamotomies performed for upper extremity tremor were reviewed and the spatial positions of the anterior limit of ventralis posterior (VP), the thalamic-internal capsular boundary and somatotopic areas within VP plotted with respect to the midline and the place of the anterior comissure. Considerable variability was noted as to the location of these points. The surgical results following 97 of the 100 thalamotomies were evaluated at least three months after the procedure. Fifty-six of 70 patients with Parkinsonian tremor had complete abolition of their upper extremity tremor, as did 20 out of 27 patients with intention tremon. Plotting the spatial positions of the lesions in those cases in which the tremor was abolished and those cases in which tremor continued revealed little difference. However, in all of the cases in which upper extremity tremor was totally abolished, the lesion site was situated in ventralis lateralis anterior to the VP representation of the buccal commissure, thumb, or index finger. This study not only demonstrates the wide range of individual spatial variability in thalamic structures, and the necessity for neurophysiologic corroboration of radiologic information during stereotactic surgery if optimal results are to be obtained, but also suggests a somatotopic organization within ventralis lateralis
— id: 33747, year: 1978, vol: 9, page: 307, stat: Journal Article,

Stereotactic implantation of iridium192 into CNS neoplasms
Kelly PJ; Olson MH; Wright AE
1978 Dec;10(6):349-354, Surgical neurology
A new method of stereotactic implantation of Iridium192 into CNS neoplasms is presented along with a method for tumor localization by computerized axial tomography, stereotactic angiography and stereotactic serial biopsies. A case treated with this technique is presented with an encouraging short term result
— id: 33744, year: 1978, vol: 10, page: 349, stat: Journal Article,

Cerebral perfusion, vascular spasm, and outcome in patients with ruptured intracranial aneurysms
Kelly PJ; Gorten RJ; Grossman RG; Eisenberg HM
1977 Jul;47(1):44-49, Journal of neurosurgery
In a retrospective study of 44 patients with verified ruptured intracranial aneurysms, the results of radionuclide cerebral perfusion scintigraphy (dynamic brain scanning) and the presence or absence of arteriographic spasm were correlated with the clinical outcome. The data indicated that patients with normal dynamic scans had a better outcome as a group and following intracranial surgery than those in whom perfusion was reduced. Patients with normal perfusion had a higher incidence of preoperative rebleeding from their aneurysms, while patients with reduced perfusion had a higher incidence of infarction, especially after intracranial surgery. There was no correlation between the presence or absence of arteriographic spasm and the results of the dynamic scans, and nor correlation between the presence of absence of spasm and the outcome of the group as a whole. However, in some individual cases with severe spasm, reduced perfusion on the dynamic scan and a poor outcome were noted. It was concluded that the results of the dynamic scan correlated better with eventual patient outcome than the presence or absence of arteriographic spasm. It is therefore suggested that patients in Grades I and II with normal dynamic scans be operated on promptly to prevent rebleeding, and that surgery in patients in Grades I and II with abnormal dynamic scans be delayed until the dynamic scan returns to normal
— id: 33745, year: 1977, vol: 47, page: 44, stat: Journal Article,

Assessment of long-term memory in brain-damaged patients
Levin HS; Grossman RG; Kelly PJ
1977 Aug;45(4):684-688, Journal of consulting & clinical psychology
— id: 33748, year: 1977, vol: 45, page: 684, stat: Journal Article,

Neurologic and psychologic manifestations of decompression illness in divers
Peters BH; Levin HS; Kelly PJ
1977 Feb;27(2):125-127, Neurology
It has been widely accepted that the neurologic sequelae of decompression illness are confined to the spinal cord. Of 10 divers who gave a history of an episode of decompression illness involving the central nervous system, we found that eight had unequivocal neurologic deficits implicating multiple supraspinal lesions. Seven of these neurologically impaired divers completed a battery of neuropsychologic tests that revealed severe deficits in all cases. The findings show that diffuse and multiple central nervous system lesions result from decompression illness and demonstrate the importance and close correlation of thorough neurologic and neuropsychologic tests in assessment following diving accidents
— id: 33749, year: 1977, vol: 27, page: 125, stat: Journal Article,

Clinical picture of atypical anorexia nervosa associated with hypothalamic tumor
White JH; Kelly P; Dorman K
1977 Mar;134(3):323-325, American journal of psychiatry
— id: 33759, year: 1977, vol: 134, page: 323, stat: Journal Article,

Physiology of the basal ganglia in relation to dystonia
Grossman RG; Kelly PJ
1976 ;14(2):49-57, Advances in neurology
— id: 33756, year: 1976, vol: 14, page: 49, stat: Journal Article,

Endothelial growth factor present in tissue culture of CNS tumors
Kelly PJ; Suddith RL; Hutchison HT; Werrbach K; Haber B
1976 Mar;44(3):342-346, Journal of neurosurgery
Human endothelial cells obtained from postpartum umbilical veins and placed in primary tissue cultures were treated with media from cultures of human and experimental central nervous system tumors. Endothelial proliferation was determined by the uptake of 3H thymidine with autoradiography and represented as the thymidine labeling index (TI), which is the proportion of 3H thymidine-labeled endothelial cells to total number of cells counted. There was a marked increase in the TI when tumor-conditioned medium was added to endothelial cultures (range 28.7% to 98.3%) when compared to controls (2.1%) and endothelium with conditioned media from fibroblasts (4.5%). This study demonstrates the presence of a chemical substance produced by tumor cells which results in endothelial proliferation. The system described provides a useful assay technique for the further characterization of this endothelial growth factor
— id: 33754, year: 1976, vol: 44, page: 342, stat: Journal Article,

Aphasic disorder in patients with closed head injury
Levin HS; Grossman RG; Kelly PJ
1976 Nov;39(11):1062-1070, Journal of neurology neurosurgery & psychiatry
Quantitative assessment of 50 patients with closed head injury disclosed that anomic errors and word finding difficulty were prominent sequelae as nearly half of the series had defective scores on tests of naming and/or word association. Aphasic disturbance was associated with severity of brain injury as reflected by prolonged coma and injury of the brain stem
— id: 33750, year: 1976, vol: 39, page: 1062, stat: Journal Article,

Short-term recognition memory in relation to severity of head injury
Levin HS; Grossman RG; Kelly PJ
1976 Jun;12(2):175-182, Cortex
Short-term recognition memory for random shapes was studied in 24 patients with head injury. The severity of head injury as indexed by duration of coma was closely related to impairment in performance. Disruption of short-term recognition memory was associated with neurologic deficit, asphasic disturbance, and signs of brain stem involvement. Performance was not related to association value of the shapes irrespective of linguistic competence. The findings are discussed in relation to recent studies of continuous recognition memory after head injury and hypotheses concerning neurological dysfunction in head injury
— id: 33751, year: 1976, vol: 12, page: 175, stat: Journal Article,

Fatal paradoxical muscle embolization in traumatic carotid-cavernous fistula repair. Case report
McCormick WF; Kelly PJ; Sarwar M
1976 Apr;44(4):513-516, Journal of neurosurgery
A unique case of fatal paradoxical muscle embolism in a patient with a traumatic carotid-cavernous fistula is described. The muscle plug intended to occlude a left-sided fistula passed through the large fistula, bypassed the lungs by way of a patent foramen ovale, and embolized through the right carotid artery to lodge the internal carotid and middle cerebral arteries producing fatal brain infarction
— id: 33753, year: 1976, vol: 44, page: 513, stat: Journal Article,

In vitro demonstration of an endothelial proliferative factor produced by neural cell lines
Suddith RL; Kelly PJ; Hutchison HT; Murray EA; Haber B
1975 Nov 14;190(4215):682-684, Science
Cultured endothelial cells exhibit a six- to tenfold increase in thymidine labeling index in response to a soluble factor elaborated by clonal cell lines of neural origin. This factor, endothelial proliferation factor, appears to be a unique property of tumor cells and may mediate the vascularization of these neoplasms
— id: 33755, year: 1975, vol: 190, page: 682, stat: Journal Article,

Photically oriented conditioned reflexes elicited by electrical stimulation of the visual system in the cat
Kelly PJ; Dikmen FN; Tarkington JA
1973 Mar 15;51(4215):293-305, Brain research
— id: 33757, year: 1973, vol: 51, page: 293, stat: Journal Article,