Noel Cohen, M.D.

Does meningitis after cochlear implantation remain a concern in 2011?
Lalwani, Anil K; Cohen, Noel L
2012 Jan;33(1):93-95, Otology & neurotology
OBJECTIVE: There have been 283 cases of meningitis after cochlear implantation reported since 2002 to the CDC Database Manufacturer and User Facility Device Experience, resulting in 30 fatalities. This is the latest of a number of reports to track the continuing problem of meningitis occurring in cochlear implant users, mainly children. RESULTS: Although a number of these patients had received a device with a 2-piece electrode, the withdrawal of that particular device has not prevented further cases from occurring. There are many potential etiologic factors potentially involved in postimplantation bacterial meningitis; although some can be managed or eliminated, vaccination against the most prevalent causal organism, the streptococcus pneumoniae, seems to be a powerful tool against this uncommon but serious complication of cochlear implantation. CONCLUSION: Although up to 20 new cases of post-cochlear implantation meningitis continue to occur annually worldwide, considering the number of new devices implanted each year, it is expected that the incidence of this complication seems to be diminishing
— id: 146257, year: 2012, vol: 33, page: 93, stat: Journal Article,

Longitudinal risk of meningitis after cochlear implantation associated with the use of the positioner
Lalwani, Anil K; Cohen, Noel L
2011 Sep;32(7):1082-1085, Otology & neurotology
OBJECTIVE: : In 2002, the electrode combined with positioner was identified as a significant risk factor for postimplantation meningitis and was voluntarily discontinued by the manufacturer. The ongoing risk of meningitis with passage of time with the positioner remains unknown. The objective of this study was to determine the current risk of meningitis in patients implanted with the positioner. STUDY DESIGN: : Data regarding the date of implantation, report of meningitis, and presence or absence of risk factors for meningitis (otitis media, inner ear malformation) were obtained from the clinical database maintained by the manufacturer. RESULTS: : There were 8,329 devices implanted that may have used a positioner, yielding a cumulative postimplantation time of 74,976 patient-years. The incidence of meningitis during the 3-year spans of 1999 to 2001, 2002 to 2004, 2005 to 2007, and 2008 to 2010 was 33, 40, 11, and 2, respectively; the risk of meningitis in cases per patient-years has decreased significantly from 0.0044 at its peak in 2001 to 0.0011 in 2010. Only a single case of positioner-related meningitis 96 months or longer after implantation has been reported. More than 40% of children had otitis media within 1 week of developing meningitis; less than 10% had a history of meningitis or inner ear malformation. CONCLUSION: : The risk of meningitis with the use of positioner is highest within the first 24 months after implantation and is frequently associated with otitis media. The risk of meningitis more than 96 months after implantation is significantly reduced. Thus, the prophylactic removal of the positioner is not recommended in patients who underwent implantation more than 8 years ago
— id: 136641, year: 2011, vol: 32, page: 1082, stat: Journal Article,

Current status of bacterial meningitis after cochlear implantation
Cohen, Noel L; Hirsch, Barry E
2010 Oct;31(8):1325-1328, Otology & neurotology
Meningitis after cochlear implantation continues to be a concern. Recent studies and anecdotal reports support the belief that intracochlear trauma, lack of appropriate immunizations, and a previously used dual-component electrode predispose patients to a higher rate of contracting meningitis. In addition, a history of meningitis, cochlear dysplasia, and certain variations of surgical technique such as the cochleostomy, very young age, immunocompromise, and the presence of neural prostheses such as shunts, are all potentially predisposing factors. Because many of these factors are beyond our control, there is likely to be an inevitable baseline incidence of meningitis, perhaps related to the underlying deafness, but by controlling other factors, we can hope to minimize the incidence. Despite the efforts of multiple individuals and organizations, there continue to be new cases of meningitis, including a small number of fatalities, each year. There is recent evidence that a sizeable percentage of children with implants have not been vaccinated as suggested by governmental agencies, otolaryngologic societies, implant manufacturers, and many cochlear implant centers. Clearly, efforts must be made to ensure age-appropriate vaccination for all cochlear implant recipients
— id: 113660, year: 2010, vol: 31, page: 1325, stat: Journal Article,

TNRT profiles with the nucleus research platform 8 system
Lai, W K; Dillier, N; Weber, B P; Lenarz, T; Battmer, R; Gantz, B; Brown, C; Cohen, N; Waltzman, S; Skinner, M; Holden, L; Cowan, R; Busby, P; Killian, M
2009 ;48(9):645-654, International Journal of Audiology
This study investigates the effect of the Nucleus CI24RE implant's neural response telemetry (NRT) system, which has less internal noise compared to its predecessor, the CI24M/R implant, on the NRT threshold (TNRT) profile across the array. CI24M/R measurements were simulated by ignoring CI24RE measurements with response amplitudes below 50 uV. Comparisons of the estimated TNRTs from the CI24RE measurements and the CI24M/R simulations suggest that, apart from a constant level difference, the TNRT profiles from the newer implant generally would not have differed very much from those of its predecessor. This view was also reflected by principal component analysis (PCA) results which revealed a 'shift' component similar to that reported by Smoorenburg et al (2002). On the whole, there is no indication that current practices of using the TNRT profiles for assisting with speech processor programming need to be revised for the CI24RE implant
— id: 141149, year: 2009, vol: 48, page: 645, stat: Journal Article,

Retrosigmoid approach for acoustic tumor removal. 1992
Cohen, Noel L
2008 Apr;19(2):239-50, vi, Neurosurgery clinics of North America
The retrosigmoid technique has evolved from the traditional suboccipital operation and, when combined with removal of the posterior wall of the internal auditory canal (IAC), affords a wide exposure of the cerebellopontine angle. This approach may be used for acoustic neuromas of all sizes, from intracanalicular, to more than 4 cm from the porus acusticus. Hearing preservation may be attempted and is generally successful in a substantial minority of cases. The facial nerve is readily visualized at the lateral end of the IAC and is at no greater risk than in the translabyrinthine operation. The authors use this approach for all hearing preservation surgery as well as for tumors of more than 3 cm, regardless of hearing
— id: 93310, year: 2008, vol: 19, page: 239, stat: Journal Article,

The totally implantable cochlear implant
Cohen, Noel
2007 Apr;28(2 Suppl):100S-101S, Ear & hearing
The concept of a totally implantable cochlear implant (TICI) offers the following advantages over the present generation of semi-implantable cochlear implants. These advantages include (1) cosmetics: deafness can be "hidden," because there is no external hardware during use; (2) no external hardware (e.g., cables, speech processor) to fail or be damaged; and (3) hearing possible 24/7, during sleep, in the shower, and while swimming. The TICI would incorporate all of the current external hardware within the buried device itself. There would also have to be external hardware for recharging the batteries and to serve other important diagnostic and functional purposes. All of this must be accomplished safely, without sacrificing performance.
— id: 73020, year: 2007, vol: 28, page: 100S, stat: Journal Article,

Cochlear implantation in the neurofibromatosis type 2 patient: long-term follow-up
Neff, Brian A; Wiet, R Mark; Lasak, John M; Cohen, Noel L; Pillsbury, Harold C; Ramsden, Richard T; Welling, D Bradley
2007 Jun;117(6):1069-1072, Laryngoscope
OBJECTIVE: To evaluate the long-term hearing outcomes of neurofibromatosis type 2 (NF2) patients with cochlear implants. METHODS: Retrospective analysis of cochlear implant performance in NF2 patients using open- and closed-set speech perception testing. RESULTS: Patients with NF2-associated bilateral vestibular schwannomas frequently become profoundly deaf. The aim of surgical resection should be to preserve serviceable hearing in at least one ear; however, this goal can be difficult to achieve. Frequently, tumor size or poor preoperative hearing status can require a surgical approach that leaves the patient with a profound, bilateral sensorineural hearing loss. If the cochlear nerve is preserved anatomically after vestibular schwannoma surgery, and if promontory stimulation confirms the functionality of the cochlear nerve, then cochlear implantation is an excellent option to restore hearing. We present six cochlear implant patients with NF2 who attained a significant improvement in open- and closed-set speech understanding with a mean follow-up of 7.9 (range: 5-13) years after surgery. In all but one case, the hearing results did not deteriorate over the follow-up period. CONCLUSION: Early surgical intervention for vestibular schwannomas in NF2 patients when the cochlear nerve can be spared is an important consideration to allow for possible cochlear implantation. A 6- to 8-week recovery period for the anatomically intact cochlear nerve may be necessary to obtain a positive promontory stimulation response following tumor resection and should be performed prior to cochlear implantation
— id: 107912, year: 2007, vol: 117, page: 1069, stat: Journal Article,

Revision cochlear implantation
Roland, J Thomas Jr; Huang, Tina C; Cohen, Noel L
2006 Aug;39(4):833-9, viii, Otolaryngologic clinics of North America
Reoperation on a patient with an indwelling cochlear implant is uncommon. When necessary, surgery is performed for explantation of an existing device with immediate or delayed reimplantation, or for scalp flap revision and receiver-stimulator repositioning in the case of infection or device migration. Rarely, revision surgery is performed to reintroduce intracochlear electrodes that may have partly or entirely extruded from the cochlea or were placed inappropriately. Successful revision cochlear implant surgery requires attention to certain surgical principles. Good outcomes, asa measured by speech perception tests, are common, but are not guaranteed. This article outlines the indications for revision cochlear implant surgery, the recommended surgical principles, and published outcomes from reimplantation
— id: 105545, year: 2006, vol: 39, page: 833, stat: Journal Article,

Combined microtia and aural atresia: issues in cochlear implantation
Lin, Karen; Marrinan, Michelle S; Shapiro, William H; Kenna, Margaret A; Cohen, Noel L
2005 Jan;115(1):39-43, Laryngoscope
OBJECTIVES: This article presents the first report of cochlear implantation in a patient with congenital aural atresia, microtia, dysplastic cochlea and internal auditory canals, and bilateral profound sensorineural hearing loss (HL). This rare combination requires special management considerations. Preoperative issues include thorough evaluation of computed tomography and magnetic resonance imaging to determine favorable anatomy, cochlear implantation candidacy, and surgical planning. Intraoperative concerns include incision placement, surgical approach to the middle ear, and abnormal facial nerve anatomy. Postoperative use of a special headset combining a microphone and transmitter coil is required. STUDY DESIGN: Case report and literature review. METHODS: The patient's chart was reviewed for diagnostic studies, operative strategy, and postoperative auditory stimulation and testing. A literature review was performed. RESULTS: A 2-year-old male presented with bilateral aural atresia, microtia, and profound sensorineural HL. Imaging studies revealed multiple abnormalities of the cochlea, vestibule, and internal auditory canal, all of which were more favorable on the right side. An incision was designed to accommodate future microtia repair. The cochlear implant was placed without difficulty by way of a facial recess approach to the middle ear. Postoperative results include the detection of Ling sounds and voices in the environment as well as the ability to locate sounds. CONCLUSIONS: This is the first report of cochlear implantation in a patient with bilateral aural atresia, microtia, and profound sensorineural HL in conjunction with multiple inner ear abnormalities. Close collaboration among the otologist, neuroradiologist, and plastic surgeon is essential to coordinate surgical management and optimize cosmetic and functional outcomes in this unique population
— id: 107913, year: 2005, vol: 115, page: 39, stat: Journal Article,

Evaluation of the neural response telemetry (NRT) capabilities of the nucleus research platform 8: initial results from the NRT trial
Battmer, Rolf D; Dillier, Norbert; Lai, Wai K; Weber, Benno P; Brown, Carolyn; Gantz, Bruce J; Roland, J Thomas; Cohen, Noel J; Shapiro, William; Pesch, Joerg; Killian, Matthijs J; Lenarz, Thomas
2004 Dec;43 Suppl 1:S10-S15, International Journal of Audiology
The purpose of this study was to evaluate the performance of the new features of the Nucleus Research Platform 8 (RP8), a system developed specifically for research purposes The RP8 consists of a research implant, a speech processor and a new NRT software (NRT v4), and includes comparisons of the different artefact-cancellation methods, NRT threshold, and recovery function measurements. The system has new artefact-suppression techniques and new diagnostic capabilities; their performance has been verified in animal experiments. In this study, NRT data were collected from 15 postlingually deafened adult cochlear implant patients intraoperatively and up to 6 months postoperatively after switch-on. The initial investigation in two clinics in Europe focused primarily on the enhanced NRT capabilities Results from the trial in two European clinics indicate that NRT measurements can be obtained with lower noise levels. A comparison of the different artefact-cancellation techniques showed that the forward-masking paradigm implemented in the Nucleus 3 system is still the method of choice. The focus of this report is on recovery function characteristics, which may give insight into auditory nerve fiber properties with regard to higher stimulation rates
— id: 105546, year: 2004, vol: 43 Suppl 1, page: S10, stat: Journal Article,

Cochlear implant candidacy and surgical considerations
Cohen, Noel L
2004 Jul-Aug;9(4):197-202, Audiology & neuro-otology
Numerous changes continue to occur in regard to cochlear implant candidacy. In general, these have been accompanied by concomitant and satisfactory changes in surgical techniques. Together, this has advanced the utility and safety of cochlear implantation. Most devices are now approved for use in patients with severe to profound rather the prior requirement of a bilateral profound loss. In addition, studies have begun utilizing short electrode arrays for shallow insertion in patients with considerable low frequency residual hearing. This technique will allow the recipient to continue to use acoustically amplified hearing for the low frequencies simultaneously with a cochlear implant for the high frequencies. New hardware, such as the behind-the-ear speech processors, require modification of existing implant surgery. Similarly, the new perimodiolar electrodes require special insertion techniques. Bilateral implantation clearly requires modification of the surgical techniques used for unilateral implantation. The surgery remains mostly the same, but takes almost twice as long, and requires some modification since at a certain point, when the first device is in contact with the body, the monopolar cautery may no longer be used. Research has already begun on the development of the totally implantable cochlear implant (TICI). This will clearly require a modification of the surgical technique currently used for the present semi-implantable devices. In addition to surgically burying the components of the present cochlear implant, we will also have to develop techniques for implanting a rechargeable power supply and a microphone for the TICI. The latter will be a challenge, since it must be placed where it is capable of great sensitivity, yet not exposed to interference or the risk of extrusion. The advances in design of, and indications for, cochlear implants have been matched by improvements in surgical techniques and decrease in complications. The resulting improvements in safety and efficacy have further encouraged the use of these devices. We anticipate further changes in the foreseeable future, for which there will likely be surgical problems to solve
— id: 46160, year: 2004, vol: 9, page: 197, stat: Journal Article,

Meningitis in cochlear implant recipients: the North American experience
Cohen, Noel L; Roland, J Thomas Jr; Marrinan, Michelle
2004 Jun;25(3):275-281, Otology & neurotology
INTRODUCTION: Until recently, postimplant meningitis was infrequently reported and felt to be uncommon. However, in the spring of 2002, there was a sudden increase in the number of reported cases of postimplantation meningitis in both Europe and North America. OBJECTIVE: Because complications of surgery often tend to be underreported, we decided to survey all cochlear implant centers in North America to determine the true incidence of postimplant meningitis and to learn more about the demographics and risk factors. STUDY DESIGN: We conducted a prospective study. A survey instrument was designed asking surgeons the number of implants performed and whether they had seen any cases of meningitis after implantation. If the answer was affirmative, they were asked to respond to a 20-point questionnaire. This instrument was sent to all 401 cochlear implant centers in North America. SETTING: Tertiary care referral centers. PATIENTS: We studied all patients having received cochlear implants in North America. MAIN OUTCOME MEASURES: Number of cases of postimplant meningitis, age of patients, device used, cochlear and temporal bone abnormalities, treatment, and outcomes. RESULTS: Meningitis is more common than previously thought. Risk factors included young age, cochlear dysplasia, temporal bone abnormalities, and the use of a two-part electrode system. This survey led to the involvement by the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention in a much more intensive analysis of a subset of the cases. CONCLUSIONS: Postimplant meningitis is related to patient, surgical, and device factors. By being aware of the risk factors involved, adhering to sound surgical principles such as packing of the cochleostomy with soft tissue, appropriately vaccinating patients, and eliminating any potentially traumatic electrode arrays, the incidence of meningitis should be significantly diminished
— id: 46169, year: 2004, vol: 25, page: 275, stat: Journal Article,

Prevention and management of cerebrospinal fluid leak following vestibular schwannoma surgery
Fishman, Andrew J; Marrinan, Michelle S; Golfinos, John G; Cohen, Noel L; Roland, J Thomas Jr
2004 Mar;114(3):501-505, Laryngoscope
OBJECTIVES/HYPOTHESIS: Postoperative cerebrospinal fluid (CSF) leak is reported in 2% to 30% of cases following vestibular schwannoma surgery. The authors' current surgical techniques for translabyrinthine, retrosigmoid transmeatal, and middle cranial fossa approaches have evolved from analysis of their prior experience in an effort to minimize their complication rate. The authors evaluated the efficacy of their current surgical technique in decreasing the postoperative CSF leak rate. STUDY DESIGN: Retrospective review. METHODS: The vestibular schwannoma database from the New York University Medical Center (New York, NY) neurotological service was reviewed. Data were extracted for type of approach, tumor size, and CSF leak rate. Liberal leak criteria were used. Surgical techniques and management of CSF leak were reviewed. RESULTS: Data from 215 patients who had surgery from 1995 to 2000 manifested a 6.6% CSF leak rate for primary surgeries. This compared favorably with the authors' 17% overall CSF leak rate in 555 total primary surgeries performed between 1979 and 1995. Translabyrinthine closure was performed with dural sutures used as a sling across the posterior fossa dura and abdominal fat placed as a series of corks through the sutures. Abdominal fat was used to obliterate the mastoid cavity in conjunction with aditus and mastoid obliteration. Attention must be paid to soft tissue obliteration of potentially open air cell tracts. Retrosigmoid transmeatal closure was performed with a soft tissue graft in the internal auditory canal drill-out held in position by a 'saloon-door' dural flap. Bone wax was used to block perimeatal cells in all cases. Watertight dural closure was achieved with a sutured temporalis fascia graft. Abdominal fat obliteration of the mastoidectomy cavity was performed with an additional firm pressure from the 'Palva' periosteal flap. Middle cranial fossa closure was performed with attention to potential air cell tracts of the internal auditory canal drill-out, as well as abdominal fat graft, tissue glue, and bone wax. Fibrin glue was used in all approaches to temporarily secure fat in situ. Management of CSF leaks starts with nonoperative measures including bed rest, oversewing of incisional wounds, and placement of a lumbar subarachnoid spinal fluid diversion drain. If these conservative measures fail, repeat exploration is necessary and is directed at identifying and corking the cell or cells (usually perimeatal or perilabyrinthine) opening directly into the posterior fossa. CONCLUSION: Evolution in surgical techniques, with particular attention to exposed air cell tracts, abdominal fat graft, and Palva periosteal flap for closure, has had a significant effect in decreasing the author's CSF leak rate after vestibular schwannoma surgery. Conservative management was successful in approximately 50% of cases. Repeat exploration, when needed, was directed at blocking the air cell tract (usually perimeatal or perilabyrinthine) responsible for the CSF leak
— id: 44805, year: 2004, vol: 114, page: 501, stat: Journal Article,

Auditory brainstem implantation in patients with neurofibromatosis type 2
Kanowitz, Seth J; Shapiro, William H; Golfinos, John G; Cohen, Noel L; Roland, J Thomas Jr
2004 Dec;114(12):2135-2146, Laryngoscope
OBJECTIVES: Multichannel auditory brainstem implants (ABI) are currently indicated for patients with neurofibromatosis type II (NF2) and schwannomas involving the internal auditory canal (IAC) or cerebellopontine angle (CPA), regardless of hearing loss (HL). The implant is usually placed in the lateral recess of the fourth ventricle at the time of tumor resection to stimulate the cochlear nucleus. This study aims to review the surgical and audiologic outcomes in 18 patients implanted by our Skull Base Surgery Team from 1994 through 2003. STUDY DESIGN: A retrospective chart review of 18 patients with ABIs. METHODS: We evaluated demographic data including age at implantation, number of tumor resections before implantation, tumor size, surgical approach, and postoperative surgical complications. The ABI auditory results at 1 year were then evaluated for number of functioning electrodes and channels, hours per day of use, nonauditory side effect profile and hearing results. Audiologic data including Monosyllable, Spondee, Trochee test (MTS) Word and Stress scores, Northwestern University Children's Perception of Speech (NU-CHIPS), and auditory sensitivity are reported. RESULTS: No surgical complications caused by ABI implantation were revealed. A probe for lateral recess and cochlear nucleus localization was helpful in several patients. A range of auditory performance is reported, and two patients had no auditory perceptions. Electrode paddle migration occurred in two patients. Patient education and encouragement is very important to obtain maximum benefit. CONCLUSIONS: ABIs are safe, do not increase surgical morbidity, and allow most patients to experience improved communication as well as access to environmental sounds. Nonauditory side effects can be minimized by selecting proper stimulation patterns. The ABI continues to be an emerging field for hearing rehabilitation in patients who are deafened by NF2
— id: 47764, year: 2004, vol: 114, page: 2135, stat: Journal Article,

Degree of modiolar coiling, electrical thresholds, and speech perception after cochlear implantation
Marrinan, Michelle S; Roland, J Thomas Jr; Reitzen, Shari D; Waltzman, Susan B; Cohen, Lawrence T; Cohen, Noel L
2004 Jun;25(3):290-294, Otology & neurotology
OBJECTIVE: Perimodiolar electrode arrays were developed to improve stimulation of specific neural populations and to decrease power consumption. Postoperative radiographs suggest that some arrays are more tightly coiled than others. The purpose of this study was to evaluate whether the degree of modiolar coil correlates with electrical threshold and/or performance measures postimplantation with the Nucleus CI24RCS (Contour) device. STUDY DESIGN: Retrospective review. SETTING: Cochlear implant center and a tertiary care hospital. PATIENTS: Twenty-eight adult cochlear implant recipients with normal cochlear anatomy who underwent implantation with the Nucleus C124RCS perimodiolar electrode and are at least 1 year postimplantation. INTERVENTIONS: Therapeutic. MAIN OUTCOME MEASURES: Radiologic degree of perimodiolar electrode placement (determined by a computer algorithmic analysis) compared with electrical thresholds and standard speech perception outcome measures at 1 year postcochlear implantation. RESULTS: No significant correlations were found between the degree of modiolar coiling of the electrode array and electrical thresholds and speech perception outcome measures at 1 year postcochlear implantation. CONCLUSIONS: The degree of coiling of a modiolar hugging electrode array was not directly correlated with the level of electrical thresholds or postoperative speech perception outcome measures. Appearance of coil tightness on postoperative radiographs could reflect either differences in array placement or intrinsic variations in cochlear anatomy, and variations in speech perception performance can be influenced by other factors, including length of deafness
— id: 46168, year: 2004, vol: 25, page: 290, stat: Journal Article,

Cochlear reimplantation in children: soft signs, symptoms and results
Waltzman, Susan; Roland, J Thomas Jr; Waltzman, Michael; Shapiro, William; Lalwani, Anil; Cohen, Noel
2004 Dec;5(4):138-145, Cochlear Implants International
OBJECTIVES: Cochlear implant device failures and reimplantation have mainly been reported on in adults. The purpose of this study was to isolate precursors of device failures and assess the effects of reimplantation in children. METHODS: From 1997 to 2003, 27 children underwent cochlear reimplantation at our institution. The pre-failure complaints were categorized and correlated with actual failure modes and postimplantation results. Speech-recognition tests were used to evaluate pre- and post-reimplantation performance. RESULTS: Pre-failure length of usage ranged from 0 to 12 years. Symptoms including pain, intermittence, reduced performance, noise and the need for frequent device adjustments were associated with device failures, although not with a particular mode of failure. Post reimplantation performance was equal to but not immediately better than pre-failure results in children who received upgraded devices. CONCLUSIONS: Specific complaints, frequent need for device adjustments and reduced speech recognition can be precursors to device failures, underscoring the need for routine follow-up evaluations. Reimplantation with newer technology does not guarantee improved speech understanding and often requires an adjustment period to reach pre-reimplantation levels.
— id: 105540, year: 2004, vol: 5, page: 138, stat: Journal Article,

Fluoroscopically assisted cochlear implantation
Fishman, Andrew J; Roland, J Thomas Jr; Alexiades, George; Mierzwinski, Jozef; Cohen, Noel L
2003 Dec;24(6):882-886, Otology & neurotology
HYPOTHESIS: Real-time intraoperative fluoroscopy is a useful adjunct to cochlear implantation in selected cases. The advantages include the avoidance of complications such as extracochlear array placement, intrameatal array insertion, and avoidance of significant bending or kinking. This is particularly useful when implanting a severely abnormal cochlea. BACKGROUND: The technique was initially developed for laboratory study of electrode prototypes in cadaver temporal bones to evaluate insertion dynamics and mechanisms of intracochlear trauma. The technique was subsequently adapted for use in live surgeries. METHODS: Live surgeries were performed using fluoroscopic guidance on nine patients. RESULTS: Five patients were implanted with the Nucleus 24 RCS during preclinical trials. Two patients with severe cochlear malformations were implanted with a Nucleus CI24M straight array. Two patients with severe cochlear ossification were implanted with the Nucleus CI24 double array. Appropriate insertions were achieved without electrode damage in all cases. CONCLUSIONS: Intraoperative fluoroscopy is a useful adjunct to cochlear implantation, which can be performed with minimum risk to the patient and operating room staff if the outlined precautions are taken. Intraoperative fluoroscopy is indicated in cases where the intracochlear behavior of the electrode array cannot be predicted, a condition encountered when implanting new electrode designs, cases with severely malformed inner ears, or cases of severe intraluminal obstruction requiring a double-array insertion
— id: 46078, year: 2003, vol: 24, page: 882, stat: Journal Article,

Second oral language capabilities in children with cochlear implants
Waltzman, Susan B; Robbins, Amy McConkey; Green, Janet E; Cohen, Noel L
2003 Sep;24(5):757-763, Otology & neurotology
OBJECTIVE: The development of oral language in children with a cochlear implant is dependent on numerous factors. Although baseline achievements have been established, ceiling attainment levels have yet to be explored. One indicator of a higher capability level is the ability of children with implants to learn to communicate orally using a second language. The purpose of this research was to explore 1) the feasibility of children with cochlear implants developing oral fluency in a second language and 2) the factors that affect the development. STUDY DESIGN: Retrospective study of children fulfilling the criteria. SETTING: University medical center. PATIENTS: Eighteen profoundly hearing-impaired children who were reported to be bilingual. INTERVENTION: Cochlear implantation at age 5 or younger. MAIN OUTCOME MEASURES: The subjects were evaluated using standard speech perception and receptive and expressive language measures. RESULTS: The data revealed the ability of some pediatric cochlear implant recipients to develop competency in a second spoken language in addition to their primary language. Equally as important is the fact that the majority showed age-appropriate receptive and/or expressive language abilities in their primary language commensurate with normal-hearing children. CONCLUSION: High levels of achievement including the learning of a second spoken language are possible after implantation in the pediatric population. Variables include speech perception postimplantation, the linguistic environment, type of intervention, and educational placement
— id: 39063, year: 2003, vol: 24, page: 757, stat: Journal Article,

Surgical technique for the Nucleus Contour cochlear implant
Cohen, Noel L; Roland, J Thomas Jr; Fishman, Andrew
2002 Feb;23(1 Suppl):59S-66S, Ear & hearing
This paper deals with the Nucleus C124R (CS) (Contour) cochlear Implant: its characteristics, differences compared with the previous generation of devices, the perimodiolar electrode, and the surgical technique used for safe insertion. We also discuss the rationale behind perimodiolar electrodes in general, as well as the results of laboratory studies validating the design and safety of this particular electrode array. The differences in surgical technique between this device and prior Nucleus cochlear implants are as follows: the incision and the size of the well, or recess, for the electronics are smaller; the cochleostomy is larger; the posterior portion is placed in a subpericranial pocket, not tied down, before electrode insertion; and the insertion process itself is quite different, due to the nature of the electrode, its size, shape, and stylet. The technique described is that used by one experienced cochlear implant center, and reflect the authors' practice. Clearly, there are other possible variations on this theme, which may be equally satisfactory in other hands. Most surgeons find this device to be easier to place than previous generations: complications to date have been uncommon
— id: 105548, year: 2002, vol: 23, page: 59S, stat: Journal Article,

Long-term effects of cochlear implants in children
Waltzman, Susan B; Cohen, Noel L; Green, Janet; Roland, J Thomas Jr
2002 May;126(5):505-511, Otolaryngology, head & neck surgery
OBJECTIVE: Since 1987, when the use of multichannel cochlear implants was initiated in children, candidacy has expanded; many thousands of children have received these devices, and results have revealed a wide range of performance. However, few long-term studies exist on a large population of these children. There have been concerns expressed that cochlear implant function might degrade over time, that devices and electrodes might migrate and extrude in the growing child, or that there might even be a deleterious effect of long-term stimulation of the cochlear nerve. The purpose of this study was to explore the long-term effects of implantation as a function of performance over time, reimplantation, and educational factors. STUDY DESIGN AND SETTING: We studied 81 children who received implants at a major academic medical center and were followed for 5 to 13 years. RESULTS: Results revealed significant gains in speech perception, use of oral language, and ability to function in a mainstream environment. There was no decrease in performance over time and no significant incidence of device or electrode migration or extrusion, and device failure did not cause a deterioration in long-term outcome. CONCLUSIONS: Multichannel cochlear implants in children provide perception, linguistic, and educational advantages, which are not adversely affected by long-term electrical stimulation
— id: 32132, year: 2002, vol: 126, page: 505, stat: Journal Article,

Delayed implantation in congenitally deaf children and adults
Waltzman, Susan B; Roland, J Thomas Jr; Cohen, Noel L
2002 May;23(3):333-340, Otology & neurotology
OBJECTIVE: To determine the efficacy of cochlear implants with current processing strategies in children and adults with long-term congenital deafness, and to determine whether the growth of auditory perceptual skills in these patients is similar to the data reported for patients who have undergone implantation with earlier devices and coding strategies. STUDY DESIGN: A prospective study of children and adults fulfilling the study inclusion criteria. SETTING: University medical center. PATIENTS: Thirty-five congenitally deaf children who received implants after the age of 8 years and 14 congenitally deaf adults who received implants as adults participated in this study. Length of device use ranged from 6 months to 3 years. MAIN OUTCOME MEASURES: Open set phoneme, word recognition tests, and sentence recognition tests were administered in quiet and noise auditory only conditions preoperatively and postoperatively. Changes in test scores were examined by paired t tests, and differences between groups were compared by Student's t tests. Spearman correlation coefficients were calculated to identify associations between scores and subject characteristics. A two-sided alpha of less than 0.05 was considered statistically significant. RESULTS: The results indicated significant improvement in open set speech perception skills in the children after implantation; the adults demonstrated improved mean scores on both word and sentence recognition. A shorter length of deafness correlated with better postoperative performance, but all subjects continued to improve over time. The improvement in test scores was similar between the devices, and no significant differences were detected between the different processing strategies. CONCLUSION: Children and adults with long-term congenital deafness can obtain considerable open set speech understanding after implantation. Length of deafness (age at implantation), length of device use, and mode of communication contribute to outcome
— id: 39660, year: 2002, vol: 23, page: 333, stat: Journal Article,

Cochlear reimplantation: surgical techniques and functional results
Alexiades G; Roland JT Jr; Fishman AJ; Shapiro W; Waltzman SB; Cohen NL
2001 Sep;111(9):1608-1613, Laryngoscope
OBJECTIVES/HYPOTHESIS: The most common indication for cochlear reimplantation is device failure. Other, less frequent indications consist of 'upgrades' (e.g., single to multichannel), infection, and flap breakdown. Although the percentage of failures has decreased over time, an occasional patient requires reimplantation because of device malfunction. The varying designs of internal receiver/stimulators and electrode arrays mandate an examination of the nature and effects of reimplantation for the individual designs. The purpose of the current study was to investigate the reimplantation of several implant designs and to determine whether differences in surgical technique, anatomical findings, and postoperative performance exist. STUDY DESIGN: Retrospective chart review. METHODS: The subjects were 33 of 618 severely to profoundly deaf adults and children who had implantation at the New York University Medical Center (New York, NY) between February 1984 and December 2000. The subjects had previously had implantation with either a single-channel 3M/House (House Ear Institute, Los Angeles, CA) or 3M/Vienna (Technical University of Vienna, Vienna, Austria) device or with one of the multichannel Clarion (Advanced Bionics, Sylmar, CA), Ineraid (Smith & Nephew Richards, TN), or Nucleus (including the Contour) devices (Cochlear Corp., Englewood, CO) before reimplantation. RESULTS: Length of use before reimplantation ranged from 1 month to 13 years and included traumatic and atraumatic (electronic) failures, as well as device extrusion or infection. Results indicated that postoperative performance was either equal to or better than scores before failure. None of the devices explanted caused damage that precluded the implantation of the same or an upgraded device. These findings support the efficacy and safety of internal implant designs as related to the maintenance of a functional cochlea for the purpose of reimplantation. CONCLUSIONS: Cochlear reimplantation can be performed safely and without decrement to performance. The number of implanted electrodes at reinsertion were either the same or greater in all cases
— id: 24631, year: 2001, vol: 111, page: 1608, stat: Journal Article,

Atypical and low-grade malignant vestibular schwannomas: clinical implications of proliferative activity
Light JP; Roland JT Jr; Fishman A; Miller DC; Cohen NL
2001 Nov;22(6):922-927, Otology & neurotology
OBJECTIVE: To examine the relationship between histopathology, immunohistochemistry, and clinical behavior in atypical and low-grade malignant vestibular schwannomas. STUDY DESIGN: The study design was a retrospective case review in conjunction with a histopathologic and immunohistochemical proliferation marker study of archival specimens. DATA SOURCES: A tertiary referral center's anatomic pathology and vestibular schwannoma computerized databases. METHODS: The diagnosis of atypical or low-grade malignant vestibular schwannoma was based on the number of mitotic figures present per tumor slide. MIB1 labeling indices were used to compare the proliferative activity of the atypical and low-grade malignant groups with that in an age-matched and size-matched control group. RESULTS: Eight cases of atypical and six cases of low-grade malignant vestibular schwannoma were diagnosed from 1990 to 1998. In the atypical and low-grade malignant groups, respectively, the average patient age was 54.3 years (range, 38-74 yr) and 50 years (range, 38-72 yr), and the average total tumor size was 1.53 cm (range, 0.7-3.5 cm) and 1.55 cm (range, 1.5-2 cm). Two recurrences were identified from the low-grade malignant group, and there was one postoperative House-Brackmann Grade III facial weakness. There were no recurrences or facial palsies in the atypical group. No distant metastasis or aggressive local invasion was observed in either group. MIB1 labeling indices were significantly (p < or = 0.001) higher in the atypical (4.69%) and low-grade malignant (5.23%) groups than in the control group (1.99%). CONCLUSIONS: These findings suggest a tendency for recurrence in proliferative tumors; however, the designation of malignancy should be reconsidered
— id: 25659, year: 2001, vol: 22, page: 922, stat: Journal Article,

Long-term results of cochlear implants in children with residual hearing
Gantz, B J; Rubinstein, J T; Tyler, R S; Teagle, H F; Cohen, N L; Waltzman, S B; Miyamoto, R T; Kirk, K I
2000 Dec;185:33-36, Annals of otology rhinology & laryngology. Supplement
— id: 141145, year: 2000, vol: 185, page: 33, stat: Journal Article,

Electrode to modiolus proximity: a fluoroscopic and histologic analysis
Roland JT Jr; Fishman AJ; Alexiades G; Cohen NL
2000 Mar;21(2):218-225, American journal of otology
HYPOTHESIS: This study was conducted to evaluate the electrode to modiolus proximity of two commonly used electrodes (Nucleus and Clarion) and a new prototype electrode. BACKGROUND: Theoretical advantages of modiolus-hugging cochlear implant electrodes include reduced stimulus energy requirements, more efficient power management and longer battery life, more discreet ganglion cell population stimulation, and reduced facial nerve stimulation. METHODS: Fluoroscopic analysis and histologic surface preparation analysis of electrode position and trauma. RESULTS: The Nucleus straight electrode occupied an outer wall position in the scala tympani. The Clarion electrode occupied a more intermediate position. The actively coiling prototype electrode was modiolus hugging but caused more trauma than the other two electrodes tested. CONCLUSIONS: The optimal modiolus-hugging atraumatic intracochlear electrode does not currently exist
— id: 8521, year: 2000, vol: 21, page: 218, stat: Journal Article,

Bipolar stimulating probe for cochlear nucleus localization in auditory brain stem
Roland JT Jr; Fishman AJ; Cohen NL
Cochlear implants New York: Thieme, 2000,
— id: 2645, year: 2000, vol: , page: 373, stat: Chapter,

Shaw scalpel in revision cochlear implant surgery
Roland JT Jr; Fishman AJ; Waltzman SB; Cohen NL
2000 Dec;185(9):23-25, Annals of otology rhinology & laryngology. Supplement
The use of traditional electrocautery is prohibited in revision or replacement cochlear implant surgery because of the concern for end organ tissue damage. Additionally, electrical current spread to the malfunctioning device could interfere with an accurate cause-of-failure analysis. Clinical reports have confirmed the utility of the Shaw scalpel for dermatologic, ophthalmic, and head and neck surgery. The Shaw scalpel is a thermally activated cutting blade that provides a bloodless field through immediate capillary and small vessel hemostasis. Avoidance of wound and flap complications is of primary concern in cochlear implant surgery. The long-term wound healing compared favorably to that of other surgical cutting instruments in several experimental reports. We have routinely used the Shaw scalpel in revision cochlear implant surgery and in primary surgery whenever electrocautery was contraindicated. We have retrospectively evaluated 22 cases in which the Shaw scalpel was used for cochlear implant revision and primary surgery. The chart review included patient demographics, the indication for surgery, the contraindication for electrocautery, intraoperative surgical notes, the wound healing evaluation, the evaluation for alopecia, and postoperative speech understanding. No significant complications occurred intraoperatively, and the long-term wound healing results were no different from those obtained with conventional surgical techniques. The explanted devices were undamaged, and valuable diagnostic information could be obtained. All patients performed at or better than their preoperative levels on speech recognition testing. Our results indicate that the Shaw scalpel is a relatively safe, easy-to-use, and effective instrument
— id: 23746, year: 2000, vol: 185, page: 23, stat: Journal Article,

Comparison of electrode position in the human cochlea using various perimodiolar electrode arrays
Tykocinski M; Cohen LT; Pyman BC; Roland T Jr; Treaba C; Palamara J; Dahm MC; Shepherd RK; Xu J; Cowan RS; Cohen NL; Clark GM
2000 Mar;21(2):205-211, American journal of otology
OBJECTIVE: This study was conducted to evaluate the insertion properties and intracochlear trajectories of three perimodiolar electrode array designs and to compare these designs with the standard Cochlear/Melbourne array. BACKGROUND: Advantages to be expected of a perimodiolar electrode array include both a reduction in stimulus thresholds and an increase in dynamic range, resulting in a more localized stimulation pattern of the spiral ganglion cells, reduced power consumption, and, therefore, longer speech processor battery life. METHODS: The test arrays were implanted into human temporal bones. Image analysis was performed on a radiograph taken after the insertion. The cochleas were then histologically processed with the electrode array in situ, and the resulting sections were subsequently assessed for position of the electrode array as well as insertion-related intracochlear damage. RESULTS: All perimodiolar electrode arrays were inserted deeper and showed trajectories that were generally closer to the modiolus compared with the standard electrode array. However, although the precurved array designs did not show significant insertion trauma, the method of insertion needed improvement. After insertion of the straight electrode array with positioner, signs of severe insertion trauma in the majority of implanted cochleas were found. CONCLUSIONS: Although it was possible to position the electrode arrays close to the modiolus, none of the three perimodiolar designs investigated fulfilled satisfactorily all three criteria of being easy, safe, and atraumatic to implant
— id: 23752, year: 2000, vol: 21, page: 205, stat: Journal Article,

Cochlear implants
Waltzman SB; Cohen NL
New York : Thieme, 2000,
— id: 1802, year: 2000, vol: , page: , stat: ,

Performance of multiply handicapped children using cochlear implants
Waltzman SB; Scalchunes V; Cohen NL
2000 May;21(3):329-335, American journal of otology
OBJECTIVE: To explore the possibility of expanding implantation guidelines to include the multiply handicapped population and to determine the pattern of development of perceptual skills in deaf children who have other impairments. PATIENTS AND SETTING: The study group consisted of 31 profoundly deaf children with documented impairments in addition to deafness who were consecutively implanted. Twenty-nine of the children underwent implantation and were followed at NYU Medical Center for at least 1 year. INTERVENTIONS AND MAIN OUTCOME MEASURES: Routine audiometric measurements and closed- and open-set measures of speech perception were performed at the phoneme, word, and sentence level pre- and postoperatively. Analyses of variance were performed when possible. RESULTS: The study population showed substantial improvement after implantation in the ability to perceive phonemes, words, and sentences using audition alone. CONCLUSIONS: Multiply handicapped children obtain demonstrable benefit from cochlear implantation, with no increase in surgical complications, although the rate of growth of perceptual skills is slower than for deaf child with no additional complicating factors
— id: 11688, year: 2000, vol: 21, page: 329, stat: Journal Article,

Surgical technique for the CLARION (R) Cochlear Implant
Balkany, TJ; Cohen, NL; Gantz, BJ
1999 APR ;108(4):27-30, Annals of otology rhinology & laryngology
This paper describes a technique for implantation of the CLARION(R) Multi-Strategy(TM) Cochlear Implant based upon the authors' surgical experience with the device. Although much of the procedure is similar to many commonly performed otologic operations, including implantation of other cochlear prostheses, several device-specific modifications are highlighted. Those modifications include a substantial bony seat, facial recess, and cochleostomy, and the use of an electrode insertion tool
— id: 54092, year: 1999, vol: 108, page: 27, stat: Journal Article,

Early results using the nucleus CI24M in children
Cohen NL; Waltzman SB; Roland JT Jr; Staller SJ; Hoffman RA
1999 Mar;20(2):198-204, American journal of otology
OBJECTIVE: To report early postimplantation speech recognition results in children who received Nucleus CI24M cochlear implants. STUDY DESIGN: The study group consisted of 19 consecutively implanted children. PATIENTS AND SETTING: Congenitally deaf children (20 months to 15 years old) were implanted with the Nucleus CI24M and followed-up at New York University Medical Center for a period of 3 to 12 months. MAIN OUTCOME MEASURES: Speech perception was evaluated preoperatively and postoperatively using the Early Speech Perception (ESP) test, the Glendonald Auditory Screening Procedure (GASP) word and sentence tests, Phonetically Balanced Kindergarten (PBK) monosyllabic word lists, Common Phrases test, the Multisyllabic and Lexical Neighborhood (MLNT, LNT) tests, and the Banford-Kowal-Bench (BKB) sentence test. RESULTS: One-way analyses of variance revealed significant improvement in open-set speech recognition in children able to perform measurement tasks. CONCLUSIONS: The Nucleus CI24M cochlear implant provides significant benefit to children after short-term use
— id: 8517, year: 1999, vol: 20, page: 198, stat: Journal Article,

Implantation of patients with prelingual long-term deafness
Waltzman SB; Cohen NL
1999 Apr;177:84-87, Annals of otology rhinology & laryngology. Supplement
The purpose of this paper is to provide performance data on long-term congenitally and prelingually deafened children and adults who are implanted with the CLARION Multi-Strategy Cochlear Implant and who use the Continuous Interleaved Sampler (CIS) speech processing strategy. Open-set speech perception was assessed preoperatively and postoperatively with word and sentence recognition tests. Results indicate that a majority of subjects showed improvement from preoperative performance to the last available postoperative evaluation. These results represent a change from previously reported data on a similar population who used earlier speech processing strategies
— id: 8516, year: 1999, vol: 177, page: 84, stat: Journal Article,

A comparison of the growth of open-set speech perception between the nucleus 22 and nucleus 24 cochlear implant systems
Waltzman SB; Cohen NL; Roland JT Jr
1999 Jul;20(4):435-441, American journal of otology
OBJECTIVE: To compare the short-term development of open-set speech perception between implementations of the spectral peak (SPEAK) strategy in adults using the Nucleus 22 (N22) Spectra processor and the Nucleus 24 (N24) system with the SPrint processor. STUDY DESIGN: Two sets of patients with a follow-up period of 3 months were compared. SETTING: This study was conducted at the New York University (NYU) Medical Center. PATIENTS: Thirty-six profoundly hearing-impaired adults were included in this study. INTERVENTION: Sixteen adults received the N22 cochlear implant with the Spectra speech processor and twenty adults received the N24 cochlear implant with the SPrint speech processor. MAIN OUTCOME MEASURES: Open-set speech perception for the patients with N22 implants was evaluated preoperatively and postoperatively using the following measures: NU-6 monosyllabic words, Iowa sentences, and CID sentences. CNC words, CUNY sentences, and HINT sentences were used to assess the patients with N24 implants. RESULTS: Results revealed that the N22 and N24 cochlear implant recipients had significant open-set speech recognition 3 and 6 months after implantation. The apparent favorable absolute scores for the patients with N24 implants were equalized when a multivariate analysis was performed to account for their younger age at time of implantation and shorter length of deafness. CONCLUSIONS: The growth of open-set word and sentence recognition in similar between the N22 and N24 cochlear implants. Longitudinal studies are needed to determine if higher ceiling scores are present in the N24. Further exploration of monopolar versus bipolar stimulation is warranted
— id: 11973, year: 1999, vol: 20, page: 435, stat: Journal Article,

Primary peripheral T-cell lymphoma of the acoustic nerve
Cohen NL
1998 Jun;118(6):910-910, Otolaryngology, head & neck surgery
— id: 7534, year: 1998, vol: 118, page: 910, stat: Journal Article,

Stability of the cochlear implant array in children
Roland JT Jr; Fishman AJ; Waltzman SB; Alexiades G; Hoffman RA; Cohen NL
1998 Aug;108(8 Pt 1):1119-1123, Laryngoscope
OBJECTIVE: To determine cochlear implant electrode stability in the young patient. Electrode migration due to future skull growth was a concern that led to prohibiting implantation in children less than 2 years of age. Recently, the high level of performance achieved by young implantees has led to a re-evaluation of this lower age limit, requiring an assessment of the effects of skull growth over time. STUDY DESIGN: Prospective radiographic analysis of electrode position of cochlear implants in young children. METHODS: Twenty-seven children implanted with the Nucleus (Cochlear Corp., Denver, CO) or Clarion (Advanced Bionics Inc., Sylmar, CA) multi-channel cochlear prostheses were subjects for this study. Follow-up radiographic studies were obtained for a period of 1 month to 5 years after implantation. The age at time of implantation ranged from 14 months to 5 years. An intraoperative modified Stenver's view plain radiograph was obtained as a baseline. After implantation, on a yearly basis transorbital Stenver's and base views were obtained for comparative purposes. Additional radiographs were obtained whenever a change in performance or electrode map caused suspicion for extrusion. Electrode position was determined using a computer graphics enhancement technique whereby image contrast filters enhanced the visibility of the electrode array and surrounding bony structures. RESULTS: An analysis of the data revealed no migration of the electrode array over time. CONCLUSIONS: The confirmation of the stability of the electrode array alleviates the concern of the effects of skull growth on cochlear implantation in young children
— id: 7765, year: 1998, vol: 108, page: 1119, stat: Journal Article,

Vestibular and auditory ototoxicity
Roland JT; Cohen NL
Otolaryngology head and neck surgery St. Louis : Mosby Year Book, 1998,
— id: 2646, year: 1998, vol: , page: 3186, stat: Chapter,

Cochlear implantation in children younger than 2 years old
Waltzman SB; Cohen NL
1998 Mar;19(2):158-162, American journal of otology
OBJECTIVE: To determine the viability of giving implants to children <2 years old and to assess the development of speech perception. STUDY DESIGN: A prospective study with a follow-up period of 1-5 years. SETTING: New York University Medical Center. PATIENTS: The patients consisted of 11 consecutive profoundly deaf children, aged 14-23 months, who were given the Nucleus cochlear implant. METHODS: Closed- and open-set speech perception were assessed preoperatively and postoperatively using the following measures: Early Speech Perception (ESP) test, the Northwestern University children's perception of speech test (NU-CHIPS), the Glendonald auditory screening procedure (GASP) word and sentence tests, the phonetically balanced kindergarten (PBK) word test, common phrases test, the multisyllabic lexical neighborhood test (MLNT), and the lexical neighborhood test (LNT). RESULTS: Paired t test was used to examine changes in scores from the preoperative test interval to the last available postoperative assessment. Results indicate that all patients had significant improvement from preoperative performance to the last postoperative evaluation and were using oral language as their means of communication. There were no medical or surgical complications. CONCLUSIONS: Children <2 years old receive substantial benefit from a multichannel cochlear implant with no increase in risk when compared with older children
— id: 12150, year: 1998, vol: 19, page: 158, stat: Journal Article,

Cochlear implant soft surgery: fact or fantasy?
Cohen NL
1997 Sep;117(3 Pt 1):214-216, Otolaryngology, head & neck surgery
A basic surgical principle is to be as gentle as possible to accomplish the goals of the operation. The concept of 'soft surgery' for cochlear implants consisted of a small, localized cochleostomy and gentle electrode insertion, the hope being that by limiting damage to the inner ear, superior hearing results might be obtained. The technique includes deferring the cochleostomy until immediately before electrode insertion, use of a large burr to flatten the promontory, followed by a smaller burr to expose the endosteum, preservation of the endosteum of the scala tympani, smoothing of the bony edges with burrs and dissectors, limited opening of the scala tympani, no suctioning of perilymph, gentle electrode insertion, and potential use of a lubricant to facilitate insertion. Although this technique has a theoretic basis, is esthetically satisfying, and has been used in many cases involving the Nucleus device at multiple centers, no data are available that demonstrate its advantages. Furthermore, the Clarion device, the results of which seem to be comparable to those of the Nucleus device, requires much more extensive and potentially damaging surgery. The pros and cons of soft surgery will be discussed. Although soft surgery seems desirable to limit trauma within the cochlea, other factors such as full electrode insertion, stimulation strategy, and survival of ganglion cells may be more important predictors of successful results
— id: 12275, year: 1997, vol: 117, page: 214, stat: Journal Article,

Surgical techniques to avoid complications of cochlear implants in children
Cohen NL
1997 ;52:161-163, Advances in oto-rhino-laryngology
— id: 12420, year: 1997, vol: 52, page: 161, stat: Journal Article,

Results of speech processor upgrade in a population of Veterans Affairs cochlear implant recipients
Cohen NL; Waltzman SB; Roland JT Jr; Bromberg B; Cambron N; Gibbs L; Parkinson W; Snead C
1997 Jul;18(4):462-465, American journal of otology
OBJECTIVE: This study aimed to evaluate the change in performance when the Speak processing strategy replaced the Mpeak strategy. SUBJECTS: Twenty-one veterans who participated in the original Department of Veterans Affairs Multicenter Cochlear Implant Study, received the Nucleus F0F1F2 processor (Cochlear Corp., Englewood, CO, U.S.A.) (WSP) and were subsequently upgraded to the Mpeak (MSP) processing strategy. METHODS: Closed- and open-set speech recognition in quiet and in noise in auditory only conditions at the phoneme, word, and sentence levels were evaluated. RESULTS: Changes in audiologic parameters were evaluated using a paired t-test for related samples. Statistically significant improvements in mean scores were found for all tests and were greatest for the speech-in-noise conditions. An examination of individual data revealed that 61% of the subjects improved for tests administered in quiet, whereas up to 69% of the subjects had improved performance in noise. Subjects with no open set speech discrimination using the Mpeak strategy showed no improvement with the Speak strategy. CONCLUSIONS: Cochlear implants can provide improved performance using modifications to external speech processor hardware and software without changing the internal implant
— id: 12307, year: 1997, vol: 18, page: 462, stat: Journal Article,

Cochlear implantation in children with cochlear malformations
Hoffman RA; Downey LL; Waltzman SB; Cohen NL
1997 Mar;18(2):184-187, American journal of otology
OBJECTIVE: To address the surgical and habilitative issues raised by cochlear implantation in children with cochlear dysplasia. STUDY DESIGN: The English-language literature is reviewed and the New York University Medical Center experience with three patients is detailed. Two hundred institutions performing cochlear implants were queried by questionnaire. SETTING: Hospitals performing cochlear implantation. PATIENTS: Pediatric patients with a cochlear implant in an ear with a dysplastic cochlea. MAIN OUTCOME MEASURES: Preoperative computed tomography analysis of cochlear anatomy was compared with operative findings, complications, and postoperative device use. RESULTS: Facial nerve anatomy was anomalous in 16% of patients, and there were two surgical injuries. There were no cases of meningitis. All patients who received multichannel implants derive benefit and wear their devices. CONCLUSIONS: All degrees of cochlear dysplasia, ranging from incomplete partition to common cavity, can be safely implanted and auditory responses expected
— id: 7165, year: 1997, vol: 18, page: 184, stat: Journal Article,

Uncommon lesions presenting as tumors of the internal auditory canal and cerebellopontine angle
Kohan D; Downey LL; Lim J; Cohen NL; Elowitz E
1997 May;18(3):386-392, American journal of otology
OBJECTIVE: The aim of this study was to identify distinguishing characteristics of uncommon lesions of the cerebellopontine angle (CPA) and internal auditory canal (IAC) in order to attain the correct diagnosis and thus formulate an appropriate therapeutic protocol. STUDY DESIGN: A retrospective chart analysis was performed on all patients with surgically managed lesions of the IAC and CPA referred to neuropathology from January 1985 to April 1996. SETTING: All patients were treated by New York University faculty at a tertiary referral center. PATIENTS: Among 426 surgical cases identified, 384 patients (90.1%) with acoustic neuromas and 18 patients (4.2%) with meningiomas were excluded. The remaining 24 cases, involving 17 women and seven men with a median age of 34 years, were analyzed. INTERVENTION: Most patients underwent audiovestibular evaluations, as well as magnetic resonance imaging (MRI) and computed tomographic (CT) scanning, and all patients underwent neurotologic surgery as part of their management protocol. MAIN OUTCOME MEASURES: Correlating patient presentation, preoperative imaging, and surgical findings often identified distinguishing characteristics of unusual CPA and IAC lesions. RESULTS: Unusual lesions identified at the CPA and IAC included: four epidermoids, four lipomas, two facial neuromas, two arachnoid cysts, two choroid plexus papillomas, two metastatic adenocarcinomas, one metastatic neuroblastoma, one ependymoma, one lymphoma, one cholesterol cyst, one angioleiomyoma, one venous hemangioma, one cavernous angioma, and one pontine glioma. CONCLUSIONS: Preoperative tumor differentiation based on the patient history, physical examination, audiovestibular testing, CT, and MRI help the surgeon to formulate an appropriate treatment protocol
— id: 7183, year: 1997, vol: 18, page: 386, stat: Journal Article,

Perception and production results in children implanted between 2 and 5 years of age
Waltzman S; Cohen NL; Gomolin R; Green J; Shapiro W; Brackett D; Zara C
1997 ;52:177-180, Advances in oto-rhino-laryngology
— id: 12419, year: 1997, vol: 52, page: 177, stat: Journal Article,

Open-set speech perception in congenitally deaf children using cochlear implants
Waltzman SB; Cohen NL; Gomolin RH; Green JE; Shapiro WH; Hoffman RA; Roland JT Jr
1997 May;18(3):342-349, American journal of otology
OBJECTIVE: To assess and document the development of open-set speech recognition in congenitally deaf children implanted with the Nucleus multichannel cochlear prosthesis at < 5 years of age. STUDY DESIGN: The study group consisted of 38 consecutively chosen children in whom the decision to proceed with implantation had already been made. PATIENTS AND SETTING: Congenitally profoundly deaf children were implanted with the Nucleus multichannel cochlear implant at < 5 years of age and followed at NYU Medical Center for a period of 1-5 years. MAIN OUTCOME MEASURES: Open-set speech perception was evaluated preoperatively and postoperatively using the following: the Glendonald Auditory Screening Procedure (GASP) word subset, the GASP sentence subtest, Phonetically Balanced Kindergarten monosyllabic word lists, Common Phrases test, Multisyllabic Lexical Neighborhood test, and Lexical Neighborhood test. RESULTS: Correlation coefficients were calculated between scores at each interval and age at implantation; one-way analyses of variance were performed independently. Results showed that all subjects had significant open-set speech recognition at the time of the last postoperative evaluation. Thirty-seven of the children use oral language as their sole means of communication. CONCLUSIONS: Multichannel cochlear implants provide significant and usable open-set speech perception in congenitally deaf children given implants at < 5 years of age
— id: 12321, year: 1997, vol: 18, page: 342, stat: Journal Article,

Prognostic significance of intraoperative facial nerve stimulus thresholds
Zeitouni AG; Hammerschlag PE; Cohen NL
1997 Jul;18(4):494-497, American journal of otology
OBJECTIVE: Intraoperative facial nerve monitoring has reduced the incidence of facial nerve paralysis associated with acoustic neuroma surgery, but poor facial nerve outcomes continue to occur. Intraoperative prediction of facial nerve outcome would be advantageous in patient management and counseling. This study seeks to evaluate intraoperative facial nerve stimulus thresholds as a tool for predicting postoperative facial nerve outcome. STUDY DESIGN: This study is a prospective clinical study of the prognostic value of intraoperative stimulus thresholds. SETTING: The study was performed at a tertiary referral center. PATIENTS: There were 109 patients undergoing excision of acoustic neuromas included in this study. INTERVENTIONS: The minimum current required to stimulate the facial nerve at the brain stem was prospectively recorded after excision of the acoustic neuroma. MAIN OUTCOME MEASURES: Facial nerve outcome was evaluated by the House-Brackmann grade. RESULTS: A statistically significant relationship was found between poor initial facial nerve outcome and higher stimulus thresholds. Long-term impaired facial function was also more common in the higher stimulus group compared to that of the lower stimulus groups. CONCLUSIONS: Although these findings suggest that intraoperative stimulus thresholds have prognostic potential, other prognostic factors should also be considered and additional research is needed
— id: 12306, year: 1997, vol: 18, page: 494, stat: Journal Article,

Meningioma of the internal auditory canal
Zeitouni AG; Zagzag D; Cohen NL
1997 Aug;106(8):657-661, Annals of otology rhinology & laryngology
Meningiomas are the second most common tumor to involve the cerebellopontine angle (CPA), but controversy exists as to whether they can arise within the internal auditory canal (IAC) or whether involvement of the IAC occurs secondarily by extension from the CPA. This paper reports on a patient with an enhancing IAC meningioma that then grew and on subsequent scans was found to involve the CPA. This case demonstrates that these tumors can arise within the IAC and can grow out to involve the CPA. These findings are discussed within the context of meningioma tumor genetics and the histologic evidence for precursor cells in the IAC. The radiologic findings useful in distinguishing an acoustic neuroma from a meningioma are reviewed in the light of this case. While an enhancing mass projecting into the IAC is most often an acoustic neuroma, this radiologic findings is not pathognomonic
— id: 7289, year: 1997, vol: 106, page: 657, stat: Journal Article,

Cerebrospinal fluid drainage in the management of CSF leak following acoustic neuroma surgery
Fishman AJ; Hoffman RA; Roland JT Jr; Lebowitz RA; Cohen NL
1996 Aug;106(8):1002-1004, Laryngoscope
A retrospective analysis was performed on 174 patients operated on from 1992 to 1995 to evaluate the safety and efficacy of continuous lumbar cerebrospinal fluid drainage (CLCFD) in the management of cerebrospinal fluid (CSF) leaks following acoustic neuroma surgery. There was a 17% incidence of CSF leak. CLCFD stopped the leak in 87% of cases. There were no cases of meningitis associated with CLCFD. One deep vein thrombosis was treated without sequelae. It is concluded that CLCFD is safe and efficacious. The authors recommend that CLCFD be implemented immediately when indicated, foregoing a trial of conservative therapy. Indications and precautions are discussed
— id: 6992, year: 1996, vol: 106, page: 1002, stat: Journal Article,

Perioperative complications of transseptosphenoidal excision for pituitary adenomas
Persky, MS; Brunner, E; Cooper, PR; Cohen, NL
1996 OCT ;6(4):231-235, Skull base surgery
Although complications of transseptosphenoidal (TSS) pituitary surgery have been discussed in the literature, there has not been an analysis of complication rates related to clinical features and the nature of the tumor. A retrospective review of 366 TSS procedures (354 patients) for excision of pituitary adenomas evaluated the incidence and management of ; perioperative complications. The mortality rate was 0.82%. The most frequently encountered complications were transient diabetes insipidus (8.74%) and cerebrospinal fluid (CSF) rhinorrhea (4.10%). Other complications included exacerbation of visual acuity and visual field defects, hemorrhage, hydrocephalus, and meningitis. The factors evaluated were gender, age, tumor size, hormone secretory status, and any history of prior pituitary surgery. There was a significantly higher incidence of transient diabetes insipidus in patients with hormone-secreting tumors. Minor and total complication rates were significantly increased in microadenomas, hormone-secreting tumors, in female patients, and in patients less than 60 years of age, reflecting the increased incidence of transient diabetes insipidus in young female patients with hormone-secreting tumors. Observed intraoperative CSF leaks predisposed to postoperative CSF rhinorrhea, There were no identifiable risk factors for major complications
— id: 53371, year: 1996, vol: 6, page: 231, stat: Journal Article,

Cochlear implants in young children: ethical considerations
Cohen NL
1995 Sep;166:17-19, Annals of otology rhinology & laryngology. Supplement
— id: 6812, year: 1995, vol: 166, page: 17, stat: Journal Article,

Medical and surgical perspectives: issues in treatment and management of severe and profound hearing impairment
Cohen NL
1995 Sep;166:149-150, Annals of otology rhinology & laryngology. Supplement
— id: 6813, year: 1995, vol: 166, page: 149, stat: Journal Article,

The ethics of cochlear implants in young children
Cohen NL
1995 ;50:1-3, Advances in oto-rhino-laryngology
— id: 12840, year: 1995, vol: 50, page: 1, stat: Journal Article,

Titanium clip for cochlear implant electrode fixation
Cohen NL; Kuzma J
1995 Sep;166:402-403, Annals of otology rhinology & laryngology. Supplement
— id: 6814, year: 1995, vol: 166, page: 402, stat: Journal Article,

Influence of processing strategies on cochlear implant performance
Cohen NL; Waltzman SB
1995 Apr;165:9-14, Annals of otology rhinology & laryngology. Supplement
The development of new processing strategies has allowed for the improvement of auditory skills in cochlear implant recipients. This study examines the effects of a change in processing strategy on the individual recipients of the Nucleus cochlear prosthesis. Twenty-five subjects who had used the F0F1F2 processing strategy (WSP III) for 2 years were switched to the MPeak strategy (MSP) and retested immediately and after 3 months. Results revealed an improvement in speech recognition ability with the MPeak strategy in those subjects who were able to perceive speech with the F0F1F2 processing strategy
— id: 12790, year: 1995, vol: 165, page: 9, stat: Journal Article,

Cochlear implants: it's time to rethink
Cohen, N L; Waltzman, S B
1995 Jan;16(1):118-119, American journal of otology
— id: 97958, year: 1995, vol: 16, page: 118, stat: Journal Article,

MULTICENTER COMPARATIVE-STUDY OF COCHLEAR IMPLANTS - FINAL REPORTS OF THE DEPARTMENT-OF-VETERANS-AFFAIRS COOPERATIVE STUDIES PROGRAM - PREFACE
COHEN, NL; WALTZMAN, SB
1995 APR ;104(4):3-3, Annals of otology rhinology & laryngology
— id: 87370, year: 1995, vol: 104, page: 3, stat: Journal Article,

SURGICAL RESULTS
DOBIE, RA; JENKINS, H; COHEN, NL
1995 APR ;104(4):6-8, Annals of otology rhinology & laryngology
Cochlear implant surgery by a group of experienced surgeons proceeded without major complications. Computed tomography scans tended to underestimate cochlear obstruction, but a drill-out was infrequently required if the scan was apparently nounal
— id: 87371, year: 1995, vol: 104, page: 6, stat: Journal Article,

Efficacy of auditory brainstem response as a screening test for small acoustic neuromas
Gordon ML; Cohen NL
1995 Mar;16(2):136-139, American journal of otology
Auditory brainstem response (ABR) has been advocated as a high sensitivity screening test for acoustic neuroma. With the advent of magnetic resonance imaging (MRI), smaller size acoustic neuromas are now detectable. A prospective trial was performed to determine the sensitivity of ABR in diagnosing small acoustic neuromas. One hundred five randomly selected patients with surgically proved acoustic neuromas underwent preoperative ABR tests within 2 months of their surgery. Patients with a histologic diagnosis other than acoustic neuroma were excluded from this study. A test was considered abnormal when the interaural wave I-V latency difference was greater than 0.2 ms, the absolute wave V latency was abnormally prolonged, or there was abnormal or absent waveform morphology. Of the 105 patients tested 92 (87.6%) had abnormal ABR test, and 13 (12.4%) had completely normal waveforms and wave latencies. Eighteen patients had tumors over 2 cm in total diameter. Of these, 12 were 2.5 cm or larger and 6 were between 2.1 and 2.4 cm. All of these 18 patients had abnormal ABR tests. Of the 29 patients with tumors 1.6-2.0 cm in size, 25 (86%) had abnormal ABRs. In the 1.0-1.5 cm diameter range there were 45 patients who underwent a preoperative ABR. Of these, 40 (89%) had abnormal ABRs. Of 13 patients with tumors 9 mm or smaller, only 9 (69%) had abnormal ABR test (p < .05). Thus, it appears that ABR sensitivity decreases with tumor size and is particularly inadequate for tumors of less than 1 cm in diameter. The authors conclude that ABR is not a good screening test for smaller acoustic neuromas and recommend MRI for patients with suspected acoustic neuroma
— id: 6634, year: 1995, vol: 16, page: 136, stat: Journal Article,

Complications of cochlear implant surgery
Hoffman RA; Cohen NL
1995 Sep;166:420-422, Annals of otology rhinology & laryngology. Supplement
— id: 8076, year: 1995, vol: 166, page: 420, stat: Journal Article,

Autologous fibrin glue in the prevention of cerebrospinal fluid leak following acoustic neuroma surgery
Lebowitz RA; Hoffman RA; Roland JT Jr; Cohen NL
1995 Mar;16(2):172-174, American journal of otology
Postoperative cerebrospinal fluid (CSF) leak is a serious complication of acoustic neuroma surgery. The authors retrospectively reviewed the charts of 492 patients who underwent acoustic neuroma surgery to determine the efficacy of fibrin glue in preventing postoperative CSF leak. Thirteen of 92 patients (14%) undergoing retrosigmoid/transmeatal surgery experienced CSF leak when fibrin glue was used; 29 of 199 patients (15%) when it was not used. Nineteen of 85 patients (22%) experienced CSF leak when fibrin glue was used following translabyrinthine surgery; 23 of 116 patients (20%) when it was not used. No decrease was noted in the incidence of CSF leak following acoustic neuroma surgery with the use of autologous fibrin glue
— id: 6670, year: 1995, vol: 16, page: 172, stat: Journal Article,

Retrofacial approach to the hypotympanum
Roland JT Jr; Hoffman RA; Miller PJ; Cohen NL
1995 Feb;121(2):233-236, Archives of otolaryngology, head & neck surgery
Otologic disease often extends into the hypotympanum, posterior mesotympanum, and infralabyrinthine compartments. Surgical access to these areas can be difficult because of the proximity of the facial nerve. In patients with a normal bone anatomy, these regions can be accessed by a retrofacial approach, which spares the posterior canal wall and avoids transposition of the facial nerve. The anatomy of the hypotympanum, posterior mesotympanum, and infralabyrinthine compartments will be reviewed emphasizing gross anatomic documentation. We will detail the surgical approach to these areas along the retrofacial air cell tract, and will present an appropriate case history
— id: 12806, year: 1995, vol: 121, page: 233, stat: Journal Article,

Postoperative imaging of the multichannel cochlear implant
Shpizner BA; Holliday RA; Roland JT; Cohen NL; Waltzman SB; Shapiro WH
1995 Aug;16(7):1517-1524, AJNR. American journal of neuroradiology
PURPOSE: To present the postoperative radiographic appearance of the multichannel cochlear implant and to suggest criteria for the radiographic evaluation of postimplant patients. METHODS: One hundred forty-one patients, 73 female and 68 male, had multichannel cochlear implants inserted. One hundred thirty-five intraoperative radiographs, 31 postoperative radiographic examinations, and 10 postoperative CT examinations were retrospectively reviewed. RESULTS: In 135 patients, a Stenver's or anteroposterior projection confirmed the normal placement of the implant by demonstrating the electrodes to be regularly spaced and gently curved within the first turn of the cochlea. The insertion depth was determined by counting the number of electrodes that projected medial to the cochlear promontory. In 5 patients in whom intracochlear placement of the electrode array could not be confirmed on plain radiographs, CT demonstrated the location of the electrode array. In 3 patients with postoperative infections, CT either correctly identified or excluded the presence of a collection beneath the implant. CONCLUSION: Plain radiographs of the temporal bone are sufficient for the postoperative treatment of the majority of postimplant patients. CT should be performed when plain radiographs cannot adequately show the location of the electrode array or if postoperative infection is suspected
— id: 6867, year: 1995, vol: 16, page: 1517, stat: Journal Article,

Predictors of postoperative performance with cochlear implants
Waltzman SB; Fisher SG; Niparko JK; Cohen NL
1995 Apr;165:15-18, Annals of otology rhinology & laryngology. Supplement
One objective of the Department of Veterans Affairs study: A Prospective Randomized Study of Advanced Cochlear Implants was to attempt to identify preoperative patient characteristics that might predict postoperative performance. We studied the relationship between all preoperative factors and the 2-year postoperative performance on 24 audiological tests for 82 patients who were implanted with the Ineraid, Nucleus, or 3M/Vienna device. Results of the univariate analysis indicated that computed tomographic findings of the cochlea and round window, IQ, age at implantation, length of deafness, profound deafness, and lipreading ability weakly correlated to postoperative performance. The multivariate analysis showed age at time of implantation, IQ, and lipreading ability to be predictive of postoperative performance
— id: 12791, year: 1995, vol: 165, page: 15, stat: Journal Article,

The ethics of cochlear implants in young children
Cohen NL
1994 Jan; 15(1):1-2, American journal of otology
— id: 8608, year: 1994, vol: 15, page: 1, stat: Journal Article,

Management of facial paralysis with jump interposition graft hypoglossal-facial anastomosis with gold lid weight
Hammerschlag PE; Cohen NL; Palu R; Brudny JJ
1994 ;:S137-S139, European archives of oto-rhino-laryngology. Supplement
— id: 11740, year: 1994, vol: , page: S137, stat: Journal Article,

Long-term results of early cochlear implantation in congenitally and prelingually deafened children
Waltzman SB; Cohen NL; Gomolin RH; Shapiro WH; Ozdamar SR; Hoffman RA
1994 Nov;15 Suppl 2:9-13, American journal of otology
Cochlear implants have been shown to improve the speech perception and production skills in children. Data are available on congenitally and prelingually deafened children who were implanted at an older age, but data on children implanted below the age of 3 years are scarce. The present study examines the benefits obtained with early implantation of the young deaf child. Fourteen congenitally or prelingually profoundly hearing-impaired children were implanted before the age of 3 years, with the Nucleus multichannel cochlear prosthesis, and followed for 2-5 years. Results indicate an overall improvement in the perception of all aspects of the speech signal in the auditory-only condition with the cochlear implant. All the children use oral language as their primary mode of communication and attend regular schools. Based on the results of this investigation, the authors conclude that implantation of the young deaf child is beneficial to the development of auditory perceptual skills
— id: 8363, year: 1994, vol: 15 Suppl 2, page: 9, stat: Journal Article,

COCHLEAR IMPLANTS - REPLY
BALKANY, T; COHEN, NL; GANTZ, BJ
1993 JUN 17 ;328(24):1787-1788, New England journal of medicine
— id: 54129, year: 1993, vol: 328, page: 1787, stat: Journal Article,

Surgical complications of multichannel cochlear implants in North America
Cohen NL; Hoffman RA
1993 ;48:70-74, Advances in oto-rhino-laryngology
By paying careful attention to the details of surgical technique, many of the complications which have occurred to date may be avoided. Some, such as late electrode and receiver/stimulator migration, device failures, and late flap necrosis due to excessive magnetic forces cannot be avoided by the surgeon, but may be prevented by further advances in implant designs. Although the incidence of life-threatening complications is minimal, and that of major complications is acceptable, every effort should be made by the surgeon, audiologist and manufacturer to further diminish these problems
— id: 56511, year: 1993, vol: 48, page: 70, stat: Journal Article,

Hearing preservation in cerebellopontine angle tumor surgery: the NYU experience 1974-1991
Cohen NL; Lewis WS; Ransohoff J
1993 Sep;14(5):423-433, American journal of otology
Between 1974 and 1991, hearing preservation surgery was attempted on 161 of 476 patients with a variety of cerebellopontine (CPA) tumors, at New York University School of Medicine. This included 146 unilateral acoustic neuromas, seven meningiomas, and six cases of neurofibromatosis. The suboccipital/retrosigmoid approach was used almost exclusively. The cochlear nerve was anatomically preserved in 131 cases, 32 percent of whom had successful hearing preservation. In the most successful group, hearing was preserved in 9 of 12 patients (75%). Success was defined as a postoperative pure-tone average (PTA) or speech reception threshold (SRT) of no more than 50 dB, and a speech discrimination score (SDS) of at least 50 percent. In those patients whose preoperative hearing was worse that this, success was based on a loss of no more than 10 dB in PTA or SRT, and 10 percent in SDS. Success was dependent mostly on extracanalicular (EC) tumor size, with the smallest tumors yielding the best results. When controlled for EC size, intracanalicular size and preoperative hearing were statistically significant variables. Origin from the superior vestibular nerve was also a favorable prognostic indicator. The character and duration of hearing loss, the patient's age, and the histology of the tumor did not have prognostic value. Auditory monitoring with either auditory brainstem response (ABR) or direct eighth nerve electrodes did not have a significant impact on success. Complications were somewhat increased by attempted hearing preservation. Facial nerve function was type I or II in 93 percent of patients. Cerebrospinal fluid leaks occurred in 15 percent of cases, but only 4 percent required surgical repair. There was one death, a patient with a 2.5-cm tumor. Early in the series, when a classic long vertical nuchal incision was used, headache and neck pain were common
— id: 6336, year: 1993, vol: 14, page: 423, stat: Journal Article,

Partial insertion of the nucleus multichannel cochlear implant: technique and results
Cohen NL; Waltzman SB
1993 Jul;14(4):357-361, American journal of otology
The goal of cochlear implant surgery is to insert the entire electrode array into the scala tympani. Incomplete insertion is usually attributable to the presence of new bone formation as a result of meningitis. Surgical techniques for dealing with obstruction include various degrees of drilling of the cochlea or alternative placement of the electrode array. We evaluated the postoperative performance of eight such patients implanted with the Nucleus multichannel cochlear implant at NYU Medical Center as well as data from adults and children nationwide. Scores ranging from marginal closed-set speech discrimination to 40 percent on open-set speech recognition tests were obtained. Surgical procedure, placement, and number of electrodes as well as number of channels in use affect the ultimate performance of these patients
— id: 6338, year: 1993, vol: 14, page: 357, stat: Journal Article,

A prospective, randomized study of cochlear implants. The Department of Veterans Affairs Cochlear Implant Study Group [see comments]
Cohen NL; Waltzman SB; Fisher SG
1993 Jan 28;328(4):233-237, New England journal of medicine
BACKGROUND. Cochlear implants restore some degree of hearing in patients with severe hearing impairment, but the efficacy of different implants has not been compared. We conducted a prospective trial to compare several cochlear implants. METHODS. We studied 82 patients who were randomly assigned to receive one of three cochlear implants: the Ineraid multichannel implant (implant 1), the Nucleus multichannel implant (implant 2), and the 3M/Vienna single-channel implant (implant 3). All the patients had profound deafness, and none had derived benefit from hearing aids. The assigned device was successfully implanted in 80 patients. Twenty-four hearing tests were used to assess the patients' performance before implantation and 12 and 24 months after implantation. The tests were grouped into five categories according to their content, and a weighted composite index was developed to provide a single numerical indicator of the overall auditory response. RESULTS. All the patients were able to hear with their implants. Nineteen of the 30 patients (63 percent) who received implant 2, 18 of the 30 patients (60 percent) who received implant 1, and 1 of the 20 patients (5 percent) who received implant 3 were able to distinguish some words and sentences. The scores for the composite index were similar in the patients who received implant 1 and those who received implant 2, and were higher in both these groups than in the patients who received implant 3 (P = 0.02). When 24 patients with implant 2 were given an improved speech processor, their composite index increased significantly within 3 months (P < 0.001); their score at that time was also significantly higher (P = 0.04) than the score of the patients with implant 1 at 24 months. Age at implantation, lip-reading ability, and IQ were prognostic indicators of the patients' performance with a cochlear implant. CONCLUSIONS. Multichannel cochlear implants are superior to single-channel implants, especially for understanding speech. Changes in speech processing can improve patients' performance
— id: 13282, year: 1993, vol: 328, page: 233, stat: Journal Article,

Surgical pitfalls in cochlear implantation
Hoffman RA; Cohen NL
1993 Jul;103(7):741-744, Laryngoscope
Increasing experience with cochlear implantation has led to the identification of potential surgical pitfalls: improper patient selection, poor flap design and handling, facial nerve injury, improper electrode placement, and improper seating of the receiver stimulator. Each of these areas of potential difficulty are reviewed, emphasizing methods of avoidance and management of adverse outcome
— id: 13120, year: 1993, vol: 103, page: 741, stat: Journal Article,

Petrous jugular malposition (diverticulum)
Pappas DG Jr; Hoffman RA; Cohen NL; Holliday RA; Pappas DG Sr
1993 Nov;109(5):847-852, Otolaryngology, head & neck surgery
Jugular bulb anatomy is variable. A 'high-riding' bulb extending into the tympanic cavity is a well-described anomaly. Petrous jugular malposition (diverticulum) (PJMD), however, is rare. The relationship between PJMD and clinical symptoms is questionable because the differentiation between PJMD as an anatomic variant and pathologic process is unproved. A literature review reveals 14 previously documented cases. We report an additional four cases. Diagnostic and management dilemmas are discussed, with the importance of high-resolution CT stressed
— id: 13058, year: 1993, vol: 109, page: 847, stat: Journal Article,

The benefits of cochlear implantation in the geriatric population
Waltzman SB; Cohen NL; Shapiro WH
1993 Apr;108(4):329-333, Otolaryngology, head & neck surgery
The deterioration of speech-understanding abilities in the aged that results from factors such as reduced speed and accuracy in processing has been well documented. The purpose of this study was to evaluate whether the geriatric population could benefit from a cochlear implant, despite the possibility of reduced processing abilities. Twenty patients, ages 65 to 85 years, with bilateral profound sensorineural hearing loss received the Nucleus multichannel cochlear prosthesis at NYU Medical Center. All patients underwent extensive preoperative medical and audiologic assessments to determine candidacy. The surgical procedure was well-tolerated by all patients. Mean postoperative test results revealed significant improvements in both auditory performance and quality of life as a result of implant usage. These data support the concept that although a reduction in the processing of sensory stimulation might exist, the elderly can process a new auditory code delivered by means of a cochlear implant
— id: 8364, year: 1993, vol: 108, page: 329, stat: Journal Article,

Retrosigmoid approach for acoustic tumor removal
Cohen NL
1992 Apr;25(2):295-310, Otolaryngologic clinics of North America
The retrosigmoid technique has evolved from the traditional suboccipital operation and, when combined with removal of the posterior wall of the internal auditory canal, affords a wide exposure of the cerebellopontine angle. This approach may be used for acoustic neuromas of all sizes, from intracanalicular to more than 4 cm from the porus acusticus. Hearing preservation may be attempted and is generally successful in a substantial minority of cases. The facial nerve is readily visualized at the lateral end of the internal auditory canal and is at no greater risk than in the translabyrinthine operation. We use this approach for all hearing preservation surgery as well as for tumors of more than 3 cm, regardless of hearing
— id: 13633, year: 1992, vol: 25, page: 295, stat: Journal Article,

Cochlear implants in the management of bilateral acoustic neuromas
Hoffman RA; Kohan D; Cohen NL
1992 Nov;13(6):525-528, American journal of otology
Multichannel cochlear implants currently provide the only modality for successful auditory rehabilitation of patients with bilateral profound sensorineural hearing loss who derive no benefit from amplification. We have developed a protocol for patients with neurofibromatosis and bilateral acoustic neuromas in which every effort is made to preserve hearing in at least one ear. Failing that, the cochlear nerve is spared, potentially allowing for the insertion of a cochlear implant. We present our data on one such patient whose auditory function was restored with a Nucleus mini 22-channel cochlear implant following removal of his acoustic neuroma
— id: 13373, year: 1992, vol: 13, page: 525, stat: Journal Article,

Spontaneous temporal bone cerebrospinal fluid leak
Pappas DG Jr; Hoffman RA; Cohen NL; Pappas DG Sr
1992 Nov;13(6):534-539, American journal of otology
Eight patients with spontaneous cerebrospinal fluid leak of temporal bone origin are presented. Pertinent history and surgical findings are reviewed and contrasted with 33 previously reported patients. Unilateral ear fullness and mild hearing loss are the most common presenting symptoms. Profuse clear otorrhea following myringotomy is virtually pathognomonic. Diagnostic methods including high-resolution computed tomography, magnetic resonance imaging, and contrast cisternography are discussed. The indications for transmastoid and combined transmastoid/middle fossa surgical repairs are compared. Both surgical approaches were found to be equally effective. We favor the transmastoid as the initial approach because of simplicity, safety, and the ability to visualize both the middle fossa and posterior fossa plates as well as the middle ear
— id: 13372, year: 1992, vol: 13, page: 534, stat: Journal Article,

Sensory aids in conjunction with cochlear implants
Waltzman SB; Cohen NL; Shapiro WH
1992 Jul;13(4):308-312, American journal of otology
The use of cochlear implants in profoundly hearing-impaired individuals can restore varying degrees of auditory capabilities. Although very little auditory information is transmitted to these patients through amplification systems, we hypothesized that some of the cues obtained from sensory aids might be helpful when used in conjunction with the cochlear implant postoperatively. Eight patients implanted at NYU Medical Center, Bellevue Hospital Center, have used some sensory aid in addition to the Nucleus multichannel cochlear prosthesis. All subjects were evaluated using standard auditory tests including pure-tone and speech audiometry, portions of the Minimal Auditory Capabilities (MAC), Speech Pattern Contrast Perception (SPAC), Iowa test batteries; and the Early Speech Perception (ESP), Word Intelligibility by Picture Identification (WIPI), and Glendonald Auditory Screening Procedure (GASP), where appropriate. Subjects were evaluated under three conditions: implant alone, implant plus sensory aid, and sensory aid alone. Results indicate that the interaction between a multichannel cochlear implant and a sensory aid can provide some improved performance for adult implanted patients (i.e., they do better under the dual condition than in the implant-alone condition). Variables such as thresholds in the nonimplanted ear and usage time can affect the outcome
— id: 13545, year: 1992, vol: 13, page: 308, stat: Journal Article,

Use of a multichannel cochlear implant in the congenitally and prelingually deaf population
Waltzman SB; Cohen NL; Shapiro WH
1992 Apr;102(4):395-399, Laryngoscope
Fourteen children and three adults, each congenitally and prelinguistically deaf, received the Nucleus multichannel implant. All underwent extensive evaluations and rehabilitation. The surgery was uneventful, and no patients have been lost to follow-up. Results have shown a significant increase in auditory and speech reception and perception skills in all children. Some children have open-set speech recognition using the prosthesis alone. The adults have shown an increased awareness of sound along with minimal improvement in perceptual skills. This supports the concept that early implantation of congenitally and prelinguistically deaf individuals results in improved performance
— id: 8323, year: 1992, vol: 102, page: 395, stat: Journal Article,

SURGICAL AND SAFETY CONSIDERATIONS OF MULTICHANNEL COCHLEAR IMPLANTS IN CHILDREN
Clark, GM; Cohen, NL; Shepherd, RK
1991 Aug;12(4):S15-S24, Ear & hearing
— id: 32159, year: 1991, vol: 12, page: S15, stat: Journal Article,

The dizzy patient. Update on vestibular disorders
Cohen NL
1991 Nov;75(6):1251-1260, Medical clinics of North America
Dizziness is often a patient's shorthand description of a variety of symptoms, many of which have nothing to do with balance. Vertigo consists of an abnormal sensation of motion, whereas dysequilibrium is a disturbance of balance without necessarily a sensation of motion. A careful history usually determines the nature of the patient's presenting symptoms, and a thorough workup will often give rise to a diagnosis. Vertigo of vestibular origin may be treated with a variety of medications or, when these fail, surgery. Surgery should preserve hearing when at all possible. Balance rehabilitation is a useful modality for the patient who does not compensate spontaneously or who does not respond to the medical or surgical treatment of imbalance
— id: 13844, year: 1991, vol: 75, page: 1251, stat: Journal Article,

Complications of cochlear implant surgery in adults and children
Cohen NL; Hoffman RA
1991 Sep;100(9 Pt 1):708-711, Annals of otology rhinology & laryngology
Surgery for cochlear prosthesis insertion exposes the patient to several potential risks. We review the surgical complication experience with cochlear implants in the United States. There have been no deaths attributable to these devices, few serious major complications, and relatively few minor complications. Major complications usually have to do with surgical technique and include flap necrosis, improper electrode placement, and rare facial nerve problems. Minor complications include dehiscence of incisions, infection, facial nerve stimulation, dizziness, and pedestal problems with the Ineraid device. Complications were less frequent in children than adults and were more likely to occur in the younger children than those above the age of 7 years. Complications were still fewer in groups of patients operated on within tightly controlled protocols. There was no increased incidence of otitis media in children who received the Nucleus Mini-22 device, and no reported sequelae from such otitis when it occurred
— id: 13904, year: 1991, vol: 100, page: 708, stat: Journal Article,

Prospective randomized clinical trial of advanced cochlear implants: preliminary results of a Department of Veterans Affairs Cooperative Study
Cohen NL; Waltzman SB; Fisher SG
1991 Oct; 100(10):823-829, Annals of otology rhinology & laryngology
This study is a randomized clinical trial to compare the efficacy and safety of one single-channel implant (the 3M/Vienna intracochlear device) and two multichannel cochlear implants (the Nucleus 22-channel device and the Smith & Nephew Richards Ineraid device). Seven Veterans Administration centers are participating in the study. The patient population consists of 82 veterans with postlingual, bilateral profound sensorineural hearing losses who obtain no benefit from amplification. All potential subjects were screened with a battery of audiologic tests. The three device groups are balanced on baseline patient characteristics. One month after operation, the devices were stimulated and programmed and the patients evaluated. Follow-up evaluations were completed at 3 and 12 months poststimulation and then annually until the end of the study. The 12-month data indicate that performance with the multichannel devices is superior to that with the single-channel device
— id: 8607, year: 1991, vol: 100, page: 823, stat: Journal Article,

Cholesterol cysts of the temporal bone: diagnosis and treatment
Goldofsky E; Hoffman RA; Holliday RA; Cohen NL
1991 Mar;100(3):181-187, Annals of otology rhinology & laryngology
Cholesterol cyst (or granuloma) of the temporal bone, a recognized clinical entity distinct from cholesteatoma, is more common than previously thought. Apparently it is caused by obstruction of previously pneumatized temporal bone air cells. Surgical cure is achieved by drainage and reestablishment of normal pneumatization. This paper reviews 14 cholesterol cysts of the temporal bone, emphasizing the importance of preoperative imaging and surgical approach. Use of magnetic resonance imaging differentiates cholesterol cysts from cholesteatoma or other neoplasms. Computed tomography delineates the location of the lesion and defines temporal bone anatomy essential to surgical approach. The two studies together allow the surgeon to properly plan drainage, as in the case of a cholesterol cyst, versus excision or exteriorization, as in the case of cholesteatoma. The infralabyrinthine approach to a petrous apex cholesterol cyst is the procedure of choice when hearing preservation is desired
— id: 14109, year: 1991, vol: 100, page: 181, stat: Journal Article,

Facial nerve stimulation with cochlear implantation. VA Cooperative Study Group on Cochlear Implantation
Niparko, J K; Oviatt, D L; Coker, N J; Sutton, L; Waltzman, S B; Cohen, N L
1991 Jun;104(6):826-830, Otolaryngology, head & neck surgery
The course of the facial nerve may place it within the current field generated by an activated cochlear implant to produce incidental facial movement. We investigated the presence of facial nerve stimulation associated with cochlear implants in the VA Cooperative Study of Advanced Cochlear implants. Twelve of 82 patients enrolled in this study demonstrated facial nerve stimulation within 2 years of implant activation. Facial nerve stimulation in six patients with multiple channel implants (Nucleus or ineraid devices) either resolved spontaneously (n = 2), or was eliminated by deactivating basal (n = 2) or apical (n = 2) electrodes. Two of six patients with single-channel electrodes (3-M/Vienna devices) demonstrated facial nerve stimulation that resolved spontaneously (n = 2), resolved with lowering current output (n = 2), or was refractory to processor adjustment (n = 2). Intraoperative assessment in one of the refractory cases indicated that facial nerve stimulation resulted from current spread through the modiolus to activate the facial nerve. A variety of factors, including implant design, stimulus parameters, and local tissue impedances, may interact to produce incidental facial stimulation. Low-impedance pathways between the scala tympani and the modiolus may deserve increased recognition as an interactive factor in cochlear implant performance
— id: 141148, year: 1991, vol: 104, page: 826, stat: Journal Article,

Extracranial repair of cerebrospinal fluid otorhinorrhea
Persky MS; Rothstein SG; Breda SD; Cohen NL; Cooper P; Ransohoff J
1991 Feb;101(2):134-136, Laryngoscope
Forty-eight patients with cerebrospinal fluid leaks comprise this retrospective study. There were 39 traumatic and 9 spontaneous leaks. Nine patients were initially managed with bed rest and spinal drainage, but 3 patients in this group ultimately required surgical intervention for repair of their persistent leaks. Thirty-nine patients had surgery as initial therapy, with 33 extracranial repairs, 2 intracranial repairs, and 4 combined approaches. The extracranial approach was used in 36 of 42 patients, with an initial success rate of 86%
— id: 14139, year: 1991, vol: 101, page: 134, stat: Journal Article,

Effects of chronic electrical stimulation on patients using a cochlear prosthesis
Waltzman SB; Cohen NL; Shapiro WH
1991 Dec;105(6):797-801, Otolaryngology, head & neck surgery
Eighteen patients using the Nucleus multichannel cochlear prosthesis underwent annual evaluations for electrical thresholds, dynamic range, and speech recognition abilities for a period of 1 to 5 years. Results revealed no correlation between length of usage of a cochlear implant and electrical thresholds. The dynamic range was initially wider in the patients with open-set speech recognition, but narrowed in subsequent years. There was a correlation between length of deafness and postoperative performance
— id: 13826, year: 1991, vol: 105, page: 797, stat: Journal Article,

OTOGENIC MUNCHAUSEN SYNDROME
Cohen, NL; Breda, SD; Lebowitz, AS
1990 May;11(3):192-195, American journal of otology
— id: 31859, year: 1990, vol: 11, page: 192, stat: Journal Article,

Intraoperative monitoring of facial nerve function in cerebellopontine angle surgery
Hammerschlag PE; Cohen NL
1990 Nov;103(5):681-684, Otolaryngology, head & neck surgery
Facial nerve paralysis associated with cerebellopontine angle surgery has been reported to range up to 26% in a recent series. Various methods of intraoperatively monitoring the facial nerve have been developed to reduce the incidence of facial paralysis. We report our experience with an intraoperative monitoring technique using intramuscular EMG electrodes to detect subclinical electrical responses that were amplified and made audible to the operating surgeon after gating stimulus artifacts. A 3.6% incidence of facial paralysis in 111 consecutive cases with this intraoperative monitoring method compared with 14.5% in 207 previously unmonitored cases indicates significant reduction of this complication in cerebellopontine angle surgery (p less than 0.001). Along with this reduction in facial paralysis, an increase in the percentage of partial facial paresis was observed in the monitored group (p less than 0.05). The percentage of those with intact facial function was similar in the monitored (82.0%) and unmonitored groups (78.3%)
— id: 14300, year: 1990, vol: 103, page: 681, stat: Journal Article,

The prognostic value of round window electrical stimulation in cochlear implant patients
Waltzman, S B; Cohen, N L; Shapiro, W H; Hoffman, R A
1990 Jul;103(1):102-106, Otolaryngology, head & neck surgery
The use of preoperative round window stimulation has been advocated for its possible predictive value in cochlear implant patients. We have attempted to correlate cause of deafness, preoperative radiologic study, and postoperative stimulability and performance with preoperative stimulation. Round window stimulation procedures consisted of measurements of electrical thresholds and comfort levels, gap detection, and temporal difference limen. Radiologic studies were performed using high-resolution computerized semi-axial and coronal tomography with 1.5-millimeter overlapping cuts. Patient performance was measured using a standard audiologic test battery. Sixteen postlingually, profoundly deaf adults who received the Nucleus multichannel cochlear implant were studied. All 16 patients who responded to preoperative stimulation had acceptable CT scans for the ear operated on and stimulated postoperatively with the prosthesis. The lowest level at which a patient could reliably detect a gap between two signals ranged from 10 to 150 milliseconds, which was not predictive. For the temporal difference limen task, the patients who could reliably identify the longer of two pulses when the difference was less than 100 milliseconds did achieve varying amounts of open-set speech discrimination postoperatively. In summary, results indicate that the preoperative psychoacoustic electrical stimulation test battery provides useful information in predicting postoperative performance
— id: 141150, year: 1990, vol: 103, page: 102, stat: Journal Article,

Improvement in speech perception and production abilities in children using a multichannel cochlear implant
Waltzman, S; Cohen, N L; Spivak, L; Ying, E; Brackett, D; Shapiro, W; Hoffman, R
1990 Mar;100(3):240-243, Laryngoscope
Nine children received the Nucleus multichannel cochlear prosthesis. The preoperative evaluation consisted of assessments of auditory function, speech recognition, linguistic skills, and speech production. There were no surgical complications, and recovery in all patients was uneventful. The device was programmed 4 to 5 weeks following surgery, and all children were conditioned to the task. Postoperative training began immediately following device stimulation and is ongoing. Auditory skills and speech production scales were devised to monitor each child's progress. All children have shown varying degrees of improvement in auditory skills and speech production using the implant alone
— id: 141153, year: 1990, vol: 100, page: 240, stat: Journal Article,

Telephone speech comprehension with use of the nucleus cochlear implant
Cohen NL; Waltzman SB; Shapiro WH
1989 Aug;142:8-11, Annals of otology rhinology & laryngology. Supplement
The reported telephone usage by cochlear implant recipients has become a major issue of controversy. Although patients and clinicians report good communication skills via the telephone, no standardized tests have been used and no quantifiable results have been reported. In an effort to determine the extent to which our better-performing patients can use the telephone, we established a clinical protocol to assess their ability to recognize speech, taking into consideration the problems inherent in telephone testing. Eight cochlear implant recipients were administered the NU-6 Monosyllabic Word Test and the City University of New York Topic Related Sentences under the following listening conditions: soundfield in a soundproof suite and via telephone within the hospital, locally, and long-distance. Twenty-three percent of the patients implanted at New York University Medical Center demonstrated a significant degree of telephone communication ability
— id: 10543, year: 1989, vol: 142, page: 8, stat: Journal Article,

A medical management for Meniere's disease
Cohen, N L; Hammerschlag, P E; Hoffman, R A
1989 Jan;10(1):78-78, American journal of otology
— id: 93208, year: 1989, vol: 10, page: 78, stat: Journal Article,

Electromyographic rehabilitation of facial function and introduction of a facial paralysis grading scale for hypoglossal-facial nerve anastomosis
Brudny J; Hammerschlag PE; Cohen NL; Ransohoff J
1988 Apr;98(4):405-410, Laryngoscope
For reinnervation of facial paralysis, the XII-VII nerve anastomosis provides tone and mass contraction but rarely allows selective muscle control. The efficacy of EMG rehabilitation was evaluated in 30 patients who had no coordinated control of facial muscles. EMG signals from bilateral homologous facial muscle sites were converted into computer-compatible waveform traces and displayed on a video monitor. This facilitated modification of neuromuscular responses using behavioral shaping techniques. A six-point Facial Nerve Grading Scale was introduced for hypoglossal-facial nerve anastomosis to assess the results of EMG rehabilitation. Rehabilitation lasted from 3 to 18 months. Ten patients (33%) achieved the highest possible grading (II) with symmetry and synchrony of function and spontaneity of expression; 17 (57%) reached grade III, which allowed voluntary control of eye and mouth function; 3 (10%) showed minimal gains. It is suggested that neural plasticity allows therapeutic manipulation of central facilitory and inhibitory mechanisms, and possible unmasking of neural connections between the ipsilateral VII and XII nerve motor nuclei which leads to improved facial function
— id: 11131, year: 1988, vol: 98, page: 405, stat: Journal Article,

Cochlear implant magnet retrofit
Cohen NL; Breda SD; Hoffman RA
1988 Jun;98(6 Pt 1):684-686, Laryngoscope
An implantable magnet is now available for patients who have received the standard Nucleus 22-channel cochlear implant and who are not able to wear the headband satisfactorily. This magnet is attached in piggy-back fashion to the previously implanted receiver/stimulator by means of a brief operation under local anesthesia. Two patients have received this magnet retrofit, and are now wearing the headset with greater comfort and satisfaction. It is felt that the availability of this magnet will increase patient compliance in regard to hours of implant usage
— id: 11074, year: 1988, vol: 98, page: 684, stat: Journal Article,

Medical or surgical complications related to the Nucleus multichannel cochlear implant [published erratum appears in Ann Otol Rhinol Laryngol Suppl 1989 Sep;98(9):754]
Cohen NL; Hoffman RA; Stroschein M
1988 Sep-Oct;135:8-13, Annals of otology rhinology & laryngology. Supplement
A questionnaire was sent to 152 surgeons to survey complications associated with the implantation of the Nucleus multichannel cochlear implant. Complications were categorized as life-threatening; major, if they necessitated revision surgery; or minor, if they resolved spontaneously or with minimal treatment. A total of 55 complications occurred in 459 reported operations for an overall complication rate of 11.8%. There were no deaths, but there was one life-threatening complication, a case of meningitis. There were 23 (4.8%) major complications, most of which involved flap design or electrode insertion (and included the case of meningitis). There were 32 (7%) minor complications. Most of the complications might have been avoided by proper training, planning of the operations, and careful attention to detail. We recommend that all prospective implant surgeons attend a device-specific training course and practice in the temporal bone laboratory
— id: 10975, year: 1988, vol: 135, page: 8, stat: Journal Article,

Teflon injection for vocal cord paralysis after intracranial operation
Heller EM; Ransohoff J; Plasse H; Cohen NL
1988 Jun;22(6 Pt 1):1109-1111, Neurosurgery
Vocal cord paralysis may follow intracranial operation if the vagus nerve is damaged intraoperatively. If the resulting laryngeal incompetence is severe, hoarseness, dysphagia, and aspiration may develop. This is often followed by a pneumonitis requiring chronic gastric tube feeding. Teflon vocal cord injection has been shown to restore the sphincteric action of the larynx and enable patients to phonate and swallow properly again. Nine patients underwent this procedure for chronic aspiration and hoarseness. All had vagus injury attributable to antecedent intracranial operation, and all experienced relief of their symptoms with only minor complications. Teflon vocal cord injection is advocated as a safe, effective means of managing patients with aspiration and dysphagia secondary to vagus nerve injury
— id: 11067, year: 1988, vol: 22, page: 1109, stat: Journal Article,

Otologic disease in patients with acquired immunodeficiency syndrome
Kohan D; Rothstein SG; Cohen NL
1988 Nov-Dec;97(6 Pt 1):636-640, Annals of otology rhinology & laryngology
A 5-year retrospective study evaluating otologic disease in patients with acquired immunodeficiency syndrome (AIDS) was conducted at the New York University Medical Center-Bellevue Hospital Center. Twenty-six patients with documented otologic disease who met the Centers for Disease Control criteria for AIDS were identified and their charts were analyzed according to presenting complaints, physical examination, diagnostic modalities, pathologic condition, management, and outcome. A marked diversity of otologic diseases of varying severity was noted. The majority of patients complained of hearing loss and otalgia during their hospitalization for treatment of AIDS-related opportunistic infections. The most frequent diagnoses were otitis externa, acute otitis media, and otitis media with effusion. Sensorineural hearing loss frequently appeared to be related to ototoxic medications and neurologic infections
— id: 10896, year: 1988, vol: 97, page: 636, stat: Journal Article,

PROBLEMS AND COMPLICATIONS OF COCHLEAR IMPLANT-SURGERY
COHEN, NL; ROSENBERG, R; GOLDSTEIN, S
1987 JAN-FEB ;96(1):14-15, Annals of otology rhinology & laryngology
— id: 41735, year: 1987, vol: 96, page: 14, stat: Journal Article,

MULTICHANNEL COCHLEAR IMPLANT - THE NEW-YORK-UNIVERSITY-BELLEVUE EXPERIENCE
COHEN, NL; WALTZMAN, SB; SHAPIRO, W
1987 JAN-FEB ;96(1):139-140, Annals of otology rhinology & laryngology
— id: 41736, year: 1987, vol: 96, page: 139, stat: Journal Article,

Hypoglossal-facial nerve anastomosis and electromyographic feedback rehabilitation
Hammerschlag, P E; Brudny, J; Cusumano, R; Cohen, N L
1987 Jun;97(6):705-709, Laryngoscope
Electromyographic (EMG) feedback has been proposed to enhance rehabilitation following hypoglossal-facial nerve anastomosis. Sixteen of 25 patients who underwent hypoglossal-facial nerve anastomosis with and without postoperative EMG rehabilitation were videotaped for evaluation of facial movement by four observers unaware of these patients' rehabilitation therapy. Using a House Facial Nerve Grading System and intragroup comparison, a trend discernible in this preliminary study indicates a chance for better facial function with EMG feedback rehabilitation
— id: 93209, year: 1987, vol: 97, page: 705, stat: Journal Article,

Intraoperative real-time monitoring of brain stem facial evoked response (BFER)
Hammerschlag, P E; John, E R; Prichep, L S; Berg, H M; Cohen, N L; Ransohoff, J
1987 Jan;97(1):57-62, Laryngoscope
Injury to the facial nerve is of concern in surgery of cerebellopontine angle tumors. The crossed acoustic reflex provides a way to monitor the ipsilateral facial nerve with the auditory stimuli delivered to the contralateral side. Using the method of optimum digital filtering, it is possible to monitor the resulting brain stem facial evoked response (BFER) in real time. This paper presents preliminary experiences in more than 18 such operations monitored using this method. This preliminary study demonstrates a trend for a high (88.8%) correlation between BFER and postoperative facial nerve function. Identical latencies from simultaneous BFER and facial nerve recordings along with findings after facial nerve transection suggest that some portion of the complex BFER waveform derives from facial nerve depolarization
— id: 67631, year: 1987, vol: 97, page: 57, stat: Journal Article,

Intrasphenoidal meningoencephalocele: a case report
Myssiorek, D; Cohen, N L
1987 Nov-Dec;8(6):391-394, American journal of otolaryngology
A case of intrasphenoidal meningoencephalocele is presented, representing the eighth case report in English language literature. The major presenting symptom was retro-orbital headache. The patient also had cerebrospinal fluid rhinorrhea and a history of recurrent meningitis. Diagnosis was suspected on the basis of plain radiographs of the sinuses and was confirmed by computed tomography scan. The meningoencephalocele was reduced via a sublabial, transseptal sphenoidotomy approach with improvement of the patient's symptoms. Management and treatment of isolated sphenoid sinus lesions are discussed as well as the pathophysiology of intrasphenoidal meningoencephaloceles
— id: 73771, year: 1987, vol: 8, page: 391, stat: Journal Article,

Long-term hearing preservation after acoustic neuroma surgery
Rosenberg RA; Cohen NL; Ransohoff J
1987 Sep;97(3):270-274, Otolaryngology, head & neck surgery
The past two decades have evidenced a remarkable improvement in the capacity of otologic surgeons to treat cerebellopontine angle tumors. Advances in instrumentation because of technologic changes, coupled with better surgical training, have contributed to a highly successful rate of tumor removal. The capability to extirpate the tumor now permits the otologic surgeon to attempt simultaneous preservation of the facial and cochlear nerve functions. Just as middle ear surgery improved to the point in the 1950s that reconstruction as well as disease eradication became possible, so can surgeons now consider preservation of function of the inner ear. It is now technically feasible--in some instances--to attempt to preserve hearing in tumors of the eighth nerve. Several studies have provided evidence that the cochlear nerve can be anatomically and functionally preserved when neuromas involve either the inferior or superior vestibular nerves. However, other studies assert that grossly intact nerves may contain microscopic islands of tumor cells intermingled with nerve fibers. If viable tumor cells were allowed to remain behind, one would expect them to grow; this would result in loss of hearing function and tumor recurrence, as evidenced by computed tomography (CT) or magnetic resonance imaging (MRI). This article will discuss the issues of cochlear nerve preservation and tumor excision, and review our experience over the past decade
— id: 11379, year: 1987, vol: 97, page: 270, stat: Journal Article,

RADIOGRAPHIC IMAGING FOR THE COCHLEAR IMPLANT
ROSENBERG, RA; COHEN, NL; REEDE, DL
1987 MAY-JUN ;96(3):300-304, Annals of otology rhinology & laryngology
— id: 41697, year: 1987, vol: 96, page: 300, stat: Journal Article,

Acoustic neuroma presenting as sudden hearing loss with recovery
Berg, H M; Cohen, N L; Hammerschlag, P E; Waltzman, S B
1986 Jan;94(1):15-22, Otolaryngology, head & neck surgery
In our series of patients operated on for acoustic neuromas at New York University Medical Center between 1974 and 1983, 13% (17 of 133) had sudden hearing loss. Of these, approximately 23% (four of 17) had recovered auditory function before acoustic neuroma extirpation. Three patients spontaneously recovered, while one improved with steroid therapy. Contrast computerized tomography demonstrated a widened internal auditory canal and evidence of cerebellopontine angle tumor, respectively, in 88% and 59% of patients with sudden hearing loss and acoustic neuroma. Clinical characteristics suggesting acoustic neuroma as the cause of sudden hearing loss with or without auditory recovery could not be identified in our series. Our data support the rationale that patients with unilateral sudden hearing loss, even with recovery, must be evaluated for a possible cerebellopontine lesion
— id: 93212, year: 1986, vol: 94, page: 15, stat: Journal Article,

Acoustic neuroma surgery: an eclectic approach with emphasis on preservation of hearing. The New York University-Bellevue experience
Cohen, N L; Hammerschlag, P; Berg, H; Ransohoff, J
1986 Jan-Feb;95(1 Pt 1):21-27, Annals of otology rhinology & laryngology
During the past 10 years, 157 patients have been operated on at the New York University-Bellevue Medical Center for acoustic neuromas and other cerebellopontine angle tumors. We describe our diagnostic protocol with joint neurosurgical evaluation leading to either translabyrinthine (otology only) or suboccipital-transmeatal (combined otology-neurosurgery) surgery. The decision is made on the basis of tumor size, level of hearing, age, and health of the patient. Using these criteria, 105 suboccipital and 59 translabyrinthine operations were performed with eight patients having had two-stage operations. In 12 of 29 patients, hearing was successfully preserved. Of 18 patients with good hearing and extracanalicular tumors less than 2 cm, hearing was preserved in 11. We describe the surgical technique used in this suboccipital-transmeatal operation and present illustrative cases in detail
— id: 67635, year: 1986, vol: 95, page: 21, stat: Journal Article,

Real-time monitoring of brainstem auditory evoked response (BAER) during cerebellopontine angle (CPA) surgery
Hammerschlag, P E; Berg, H M; Prichep, L S; John, E R; Cohen, N L; Ransohoff, J
1986 Dec;95(5):538-542, Otolaryngology, head & neck surgery
The signal-to-noise ratio of brainstem auditory evoked responses (BAER) can be greatly enhanced by use of optimal digital filtering before averaging. This permits accurate assessment of auditory nerve status every 5 to 10 seconds, making real-time intraoperative monitoring possible. The major advantages yielded by real-time monitoring--in our experience thus far--have been identification of potentially adverse functional consequences of apparently uneventful surgical maneuvers, reducing postoperative dysfunction, early indication of potential for improved clinical function, and potential identification and localization of neural tissue in the face of absent surgical landmarks. Examples of these advantages will be provided from case studies, and the possibility that real-time monitoring may improve ability to preserve hearing will be discussed
— id: 67633, year: 1986, vol: 95, page: 538, stat: Journal Article,

Evaluation of a cochlear prosthesis using connected discourse tracking
Levitt, H; Waltzman, S B; Shapiro, W H; Cohen, N L
1986 Jan;23(1):147-154, Journal of rehabilitation research & development
A multichannel cochlear prosthesis was evaluated using the method of Connected Discourse Tracking. Data were obtained from five subjects over a 10-week period. Significant learning effects were obtained both with and without the prosthesis. The method of orthogonal polynomials was used to obtain a statistically precise fit for each learning curve. The curves differed both in terms of shape and average rate of learning. The two best subjects showed substantial improvements, reaching tracking rates in excess of 90 words-per-minute. A method for representing prosthesis-based improvements, which takes learning effects into account, is developed and discussed
— id: 141154, year: 1986, vol: 23, page: 147, stat: Journal Article,

Update on AIDS
Rosenberg RA; Schneider KL; Cohen NL
1986 Sep;95(2):127-130, Otolaryngology, head & neck surgery
— id: 63354, year: 1986, vol: 95, page: 127, stat: Journal Article,

Cholesteatoma vs. cholesterol granuloma of the petrous apex
Rosenberg, R A; Hammerschlag, P E; Cohen, N L; Bergeron, R T; Reede, D L
1986 Mar;94(3):322-327, Otolaryngology, head & neck surgery
Lesions involving the petrous apex are rarely encountered in clinical practice. This directly affects the ability of the otolaryngologist to diagnose and effectively treat these lesions. Greater physician awareness and increased technologic capability are leading to more effective management of pathologic conditions involving this area of the temporal bone
— id: 93211, year: 1986, vol: 94, page: 322, stat: Journal Article,

HOW I DO IT - OTOLOGY AND NEUROTOLOGY A SPECIFIC ISSUE AND ITS SOLUTION - INTRAOPERATIVE VERIFICATION OF MULTICHANNEL SCALA TYMPANI ELECTRODE POSITION
ROSENBERG, RA; COHEN, NL
1986 NOV ;96(11):1293-1294, Laryngoscope
— id: 41539, year: 1986, vol: 96, page: 1293, stat: Journal Article,

Long-term effects of multichannel cochlear implant usage
Waltzman, S B; Cohen, N L; Shapiro, W H
1986 Oct;96(10):1083-1087, Laryngoscope
A major concern regarding multichannel (multi-electrode) cochlear prosthesis usage has been the possibility of long-term deleterious physiological effects such as the degeneration of spiral ganglion cells, neuronal degeneration, and new bone formation. These effects, if present, would become evident in the deterioration of hearing sensation and performance of the cochlear implant recipient on a battery of audiologic tests. To date, five patients using the Australian multi-electrode multichannel cochlear implant have undergone a 1-year evaluation of the device. The assessment includes a check of electrical threshold and comfort levels for each electrode, sound field pure tone and speech thresholds, the MAC battery, vowel and consonant recognition tests, and speech tracking tasks. All results were compared to those obtained postoperatively following stimulation and a 3-month training period. Results to date have shown no deterioration in implant functioning in all patients tested. Periodic extensive monitoring of all implant recipients is advocated in order to evaluate the possibility of long-term effects
— id: 141155, year: 1986, vol: 96, page: 1083, stat: Journal Article,

Cricopharyngeal myotomy: a review of surgical results in patients with cricopharyngeal achalasia of neurogenic origin
Berg, H M; Jacobs, J B; Persky, M S; Cohen, N L
1985 Nov;95(11):1337-1340, Laryngoscope
Cricopharyngeal myotomy is an effective procedure for the treatment of swallowing disorders due to dysfunction of the upper esophageal sphincter and pharyngeal musculature. Eight patients with documented pharyngeal and sphincteric dysfunction have undergone myotomies with significant improvement in swallowing associated with restoration of oral feeding without aspiration in 5, while 3 patients have not improved. The preoperative work-up and evaluation is discussed as well as criteria that may identify those patients most likely to benefit from this treatment
— id: 145531, year: 1985, vol: 95, page: 1337, stat: Journal Article,

Restoration of speech discrimination following suboccipital, transmeatal excision of extracanalicular acoustic neuroma
Cohen, N L; Ransohoff, J; Jacobs, J
1985 Feb;93(1):126-131, Otolaryngology, head & neck surgery
— id: 67637, year: 1985, vol: 93, page: 126, stat: Journal Article,

Clinical trials with a 22-channel cochlear prosthesis
Cohen, N L; Waltzman, S B; Shapiro, W H
1985 Dec;95(12):1448-1454, Laryngoscope
During 1984, six patients have been implanted with a 22-channel cochlear prosthesis. The device features a programmable wearable speech processor using a speech feature encoding strategy. A strict clinical protocol was followed, and no patients have been lost to follow-up. All patients are regular users of the device and have shown a restoration of hearing sensation in response to acoustic stimuli. Pure tone averages ranged from 20 to 47 dB HL and speech detection thresholds varied from 15 to 32.5 dB HL. All patients have shown a recognition of a large variety of environmental sounds, and an improvement in speech recognition ability when the device is used in conjunction with lipreading. Speech reception thresholds using spondee words without lipreading were obtained in three patients at levels of 27.5 to 55 dB HL and one patient had an open-set speech discrimination score (w-22 word list) of 42% without lipreading. In addition, two of the patients show an ability to have limited interactive conversation without the use of lipreading
— id: 141156, year: 1985, vol: 95, page: 1448, stat: Journal Article,

INTRASPHENOIDAL MENINGOENCEPHALOCELE - DIAGNOSIS AND MANAGEMENT
COHEN, NL; MYSSIOREK, D
1985 APR ;96(4):70-70, Otolaryngology, head & neck surgery
— id: 73788, year: 1985, vol: 96, page: 70, stat: Journal Article,

Head and neck presentations of acquired immunodeficiency syndrome
Rosenberg, R A; Schneider, K L; Cohen, N L
1985 Dec;93(6):700-705, Otolaryngology, head & neck surgery
Since December 1980, over 3000 cases of acquired immunodeficiency syndrome (AIDS) have been reported. The charts of 102 patients admitted to the New York University Medical Center with a diagnosis of AIDS were reviewed with particular emphasis on presenting signs, symptoms, and laboratory values. Symptoms tended to be nonspecific and most often resembled those of an upper respiratory infection. Over 71% of the patients presented with at least two of the following four signs: diffuse adenopathy, oral and facial lesions consistent with Kaposi's sarcoma, white oral lesions, and anergy. Laboratory findings included leukopenia, increased erythrocyte sedimentation rate, thrombocytopenia, and anemia. The in-hospital mortality rate was 26%. The current status of our knowledge concerning AIDS is reviewed and discussed. The frequency and types of presenting signs and symptoms in the head and neck are reported to alert the otolaryngologic community to this entity
— id: 67500, year: 1985, vol: 93, page: 700, stat: Journal Article,

Hearing preservation--posterior fossa approach
Cohen, N L; Ransohoff, J
1984 Apr;92(2):176-183, Otolaryngology, head & neck surgery
In patients with acoustic neurinomas protruding less than 2 cm from the porus acusticus and free of the brain stem, hearing can often be preserved. Our neurosurgical/otologic team uses the combined suboccipital/transmeatal approach with the patient in the seated position. This operation has been attempted on 21 patients from 1974 to 1982. Nine had tumors larger than 2 cm that touched the brain stem; one had useful hearing preserved. Of the 12 patients with tumors smaller than 2 cm, hearing at or near the preoperative level was preserved in seven. In one patient, hearing was improved. There have been up to 7 years of follow-up with no recurrences of the neurinomas or diminution of hearing evident on computed tomographic scan. All had preservation of the seventh cranial nerve, while complications were mild and comparable to the remainder of our 101 patients operated on during the same period. We will review the surgical technique and audiologic results in detail
— id: 67639, year: 1984, vol: 92, page: 176, stat: Journal Article,

INTRASPHENOIDAL MENINGOENCEPHALOCELE - DIAGNOSIS AND MANAGEMENT
MYSSIOREK, DJ; COHEN, NL
1984 APR ;6(1):96-96, Otolaryngology, head & neck surgery
— id: 73791, year: 1984, vol: 6, page: 96, stat: Journal Article,

COMBINED TREATMENT OF HEAD AND NECK VASCULAR MASSES WITH PREOPERATIVE EMBOLIZATION
PERSKY, MS; BERENSTEIN, A; COHEN, NL
1984 ;94(1):20-27, Laryngoscope
— id: 41115, year: 1984, vol: 94, page: 20, stat: Journal Article,

Head and neck presentations of acquired immunodeficiency syndrome
Rosenberg, R A; Schneider, K L; Cohen, N L
1984 May;94(5 Pt 1):642-646, Laryngoscope
Since December 1980, over 2,000 cases of acquired immunodeficiency syndrome (AIDS) have been reported. The charts of 72 patients admitted to the New York University Medical Center with a diagnosis of AIDS were reviewed with particular emphasis on presenting signs, symptoms and laboratory values. Symptoms tended to be non-specific and most often resembled an upper respiratory infection. Over 95% of the patients presented with either diffuse adenopathy, oral or facial lesions consistent with Kaposi's sarcoma, white oral lesions, or anergy. Laboratory findings included leukopenia, increased erythrocyte sedimentation rate, thrombocytopenia and anemia. The in-hospital mortality rate was 26%. The current status of our knowledge concerning AIDS is reviewed and discussed. The frequency and types of presenting signs and symptoms in the head and neck are reported in order to alert the otolaryngologic community to this entity
— id: 67502, year: 1984, vol: 94, page: 642, stat: Journal Article,

ARTERIAL MALFORMATIONS OF THE MIDDLE-EAR
SINNREICH, AI; PARISIER, SC; COHEN, NL; BERREBY, M
1984 ;92(2):194-206, Otolaryngology, head & neck surgery
— id: 41092, year: 1984, vol: 92, page: 194, stat: Journal Article,

Pneumatic dilatation as the primary treatment for achalasia
Jacobs, J B; Cohen, N L; Mattel, S
1983 Jul-Aug;92(4 Pt 1):353-356, Annals of otology rhinology & laryngology
Pneumatic dilatation under fluoroscopic control has proven highly successful in the treatment of achalasia. This procedure involves minimal morbidity, local anesthesia is employed, and hospitalization is brief, usually only two days. Surgical myotomy of the lower esophageal sphincter, the Heller procedure, requires a thoracotomy under general anesthesia with its attendant morbidity and at least ten days of hospitalization. In addition, there is a significant incidence of postoperative gastric reflux. We have employed pneumatic dilatation as the sole primary treatment for 30 patients over the last 10 years. The results have been highly successful with marked relief of symptoms and weight gain. Pneumatic dilatation is an effective treatment for achalasia and is recommended as the initial procedure of choice
— id: 145535, year: 1983, vol: 92, page: 353, stat: Journal Article,

Platysma myocutaneous flap for intraoral defects
Persky, M S; Kaufman, D; Cohen, N L
1983 Jul;109(7):463-464, Archives of otolaryngology
The use of myocutaneous flaps has resulted in improved methods for reconstruction involving the head and neck area. The platysma myocutaneous flap offers an excellent alternative for reconstructing appropriate oral cavity defects resulting from tumor ablation. It has certain advantages over other local or distant pedicled flaps and has been proved to be a reliable alternative for single-stage repair of these defects. The technique of this flap is described and a review of its use in six cases, including complications, is discussed
— id: 148223, year: 1983, vol: 109, page: 463, stat: Journal Article,

Computed tomography of glomus tympanicum tumors
Som, P M; Reede, D L; Bergeron, R T; Parisier, S C; Shugar, J M; Cohen, N L
1983 Feb;7(1):14-17, Journal of computer assisted tomography
Previously it has been very difficult or impossible for radiologists to delineate accurately the size and extent of glomus tympanicum tumors. By utilizing axial transverse and coronal computed tomography detailed enlargement techniques we have been able to accurately demonstrate four such lesions. We believe that this mode of investigation is now the method of choice for glomus tympanicum tumors
— id: 137143, year: 1983, vol: 7, page: 14, stat: Journal Article,

Small acoustic neuromas: detection by high resolution gas CT cisternography
Pinto, R S; Kricheff, I I; Bergeron, R T; Cohen, N
1982 Jul;139(1):129-132, American journal of roentgenology
Experience with 81 gas computed tomography (CT) cisternography procedures in 79 patients in searching for acoustic neuroma is reported. Twenty-one tumors, four exclusively intracanalicular, were demonstrated after standard contrast-enhanced CT was negative. Fifty-five examinations were negative; four were inconclusive. The high resolution scanner with digital localization and reconstruction zoom capability greatly improved image detail. In nine of the 12 normal patients examined with it, the intracanalicular bundle was demonstrated. Substitution of carbon dioxide for air greatly reduced the morbidity of acute post-spinal tap headache. The procedure takes 30--45 min and can be performed on an outpatient basis. It is recommended as the procedure of choice when standard CT is negative in subjects clinically suspected of having acoustic neuroma
— id: 99482, year: 1982, vol: 139, page: 129, stat: Journal Article,

Clinical trial of halazepam and clorazepate: considerations of a single bedtime dose [proceedings]
Cohen NL; Alpert M; Friedhoff AJ
1981 Jan;17(1):134-135, Psychopharmacology bulletin
— id: 29163, year: 1981, vol: 17, page: 134, stat: Journal Article,

ABERRANT INTERNAL CAROTID-ARTERY IN THE MIDDLE-EAR
GOODMAN, RS; COHEN, NL
1981 ;90(1):67-69, Annals of otology rhinology & laryngology
— id: 50401, year: 1981, vol: 90, page: 67, stat: Journal Article,

Air-CT cisternography and canalography for small acoustic neuromas
Kricheff, I I; Pinto, R S; Bergeron, R T; Cohen, N
1980 Jan-Feb;1(1):57-63, AJNR. American journal of neuroradiology
Disenchantment with the limitations, and in some cases the morbidity, of currently used radiologic techniques for the demonstration or exclusion of small acoustic neuromas prompted development of an examination using small amounts of intrathecal air and computed tomography (CT). A prospective study was designed to evaluate air CT cisternography/canalography, wherein patients with the clinical symptoms of acoustic neuroma but with negative enhanced CT, were evaluated by metrizamide CT cisternography followed by air CT cisternography/canalography. Pantopaque cisternography was then performed as a control procedure. Four patients had surgically proven tumors. In 13 others, accumulated evidence indicated no tumors were present. Results suggest that air-CT cisternography is superior to all other diagnostic methods in defining small acoustic neuromas, and may exclude an intracanalicular lesion without the potential hazards of Pantopaque cisternography or high concentration metrizamide tomocisternography. With air-CT cisternography, there were no errors in this series
— id: 99490, year: 1980, vol: 1, page: 57, stat: Journal Article,

ACOUSTIC NEUROMA SURGERY WITH EMPHASIS ON PRESERVATION OF HEARING
Cohen, NL
1979 ;89(6):886-896, Laryngoscope
— id: 29987, year: 1979, vol: 89, page: 886, stat: Journal Article,

NEURILEMOMA OF THE TRACHEA
Nass, RL; Cohen, NL
1979 ;105(4):220-221, Archives of otolaryngology
— id: 30109, year: 1979, vol: 105, page: 220, stat: Journal Article,

Role of computerized tomography in the diagnosis of acoustic neuromas
Bergeron, R T; Cohen, N L; Pinto, R S
1977 Jun;103(6):314-317, Archives of otolaryngology
Computerized tomography has manifest usefulness in the roentgenologic identification of intracranial masses, and acoustic neuromas are no exception. Nonetheless, traditional roentgenographic examinations for the workup of acoustic neuromas should not yet be completely discarded in favor of this new modality. Computerized tomography scanning is an insensitive and unreliable technique for delineating the size and configuration of the internal acoustic canals. With current technology, it will not reliably show neuromas less than 1.5 cm in cross-sectional dimension. Technical artifacts may also contribute to false-negative and though rare to false-positive findings. The false-negative rate will be unacceptably high in the presence of small lesions if this technique is treated as a definitive examination rather than a screening one. Though uncommon, it may also be negative in the presence of relatively large lesions
— id: 99556, year: 1977, vol: 103, page: 314, stat: Journal Article,

EARS, NOSE, AND THROAT
Cohen, NL
1977 ;9(11):63-6?, Emergency medicine
— id: 29518, year: 1977, vol: 9, page: 63, stat: Journal Article,

The auditory, vestibular and renal effects of capreomycin in humans
Garfield, J W; Jones, J M; Cohen, N L; Daly, J F; McClement, J H
1966 Apr 20;135(2):1039-1046, Annals of the New York Academy of Sciences
— id: 141225, year: 1966, vol: 135, page: 1039, stat: Journal Article,

CUPULOMETRY AS AN INVESTIGATIVE TOOL
DALY, J F; COHEN, N L
1965 Apr;81:340-346, Archives of otolaryngology
— id: 141230, year: 1965, vol: 81, page: 340, stat: Journal Article,

Viomycin ototoxicity in man: a cupulometric study
Daly, J F; Cohen, N L
1965 ;53:150-163, Transactions of the American Otological Society
— id: 141232, year: 1965, vol: 53, page: 150, stat: Journal Article,

VIOMYCIN OTOTOXICITY IN MAN: A CUPULOMETRIC STUDY
DALY, J F; COHEN, N L
1965 Jun;74:521-534, Annals of otology rhinology & laryngology
— id: 141229, year: 1965, vol: 74, page: 521, stat: Journal Article,