Future of Virtual Colonoscopy
There is already a role for virtual colonoscopy in evaluating patients who have had a failed colonoscopy and in evaluating the colon near an obstructing lesion. In addition, virtual colonoscopy may be the test of choice in patients with underlying medical problems, as well as those with bleeding disorders and those who cannot undergo sedation. It is important to stress that currently only certain medical centers have expertise in the performance and interpretation of virtual colonoscopy examinations.
There are several technological developments that will improve the performance of virtual colonoscopy. Currently radiologists agree that for virtual colonoscopy to successfully detect polyps and cancers the colon needs to be cleaned and well distended. However, research into optimizing fecal tagging with subtraction techniques may, in the future, allow virtual colonoscopy to be done without a bowel preparation. In addition, there is a great deal of interest in computer-aided detection (CAD) and diagnosis that may increase the ability of the virtual colonoscopy to detect colorectal polyps (59). The hope is that CAD will be used as a second read, increasing the success rate of virtual colonoscopy in polyp detection. Initial studies have shown that up to 90 percent of polyps greater than 6mm may be detected with the aid of CAD. In summary, the future of virtual colonoscopy is very promising. For the procedure to be widely used in the future, more clinicians need to be trained in all aspects of performing virtual colonoscopy, including patient preparation, data acquisition and perhaps most importantly, data interpretation.