9520388 Vining Colorectal carcinoma is the second leading cause of cancer deaths in the United States. As with other cancers, studies suggest that early detection and removal of precursor polyps and small carcinomas reduces mortality. Visualization of the entire colon by means of X-ray images enhanced with barium (a barium enema) or colonoscopy (endoscope) improves polyp detection. Both examinations have poor patient compliance because of associated discomfort, inconvenience, risk and cost. colonoscopy has an advantage over barium enema because it serves both as a diagnostic test and a therapeutic procedure, as polyps are removed upon their discovery. However, colonoscopy is an invasive examination, does not always reveal significant lesions, fails to reach the far end (cecum) of the colon in about 15% of patients, sometimes requires sedation, increases the risk of bowel perforation, and is the most expensive of all bowel examinations. This proposal describes research to develop a new approach for Virtual Colonoscopy (VC) examinations as a substitute for the costly and invasive diagnostic colonoscopy (DC). VC combines helical CT scanning, 3D reconstruction, and high- performance computing to examine the entire colon rapidly and to lessen the discomfort for the patient. The aims of this project are to generate new software for evaluating VC examinations, to create an algorithm for measuring the colon's wall thickness to highlight areas of abnormal thickness, to validate the accuracy of VC with the foregoing modifications, and to determine the cost-savings potential of VC relative to DC. The project involves a multidisciplinary team of investigators, the results are to be evaluated in a clinical setting by comparing the results of VC relative to DC in patients undergoing usual care colonoscopy, and the work plan includes educational activities to promote a better understanding of the cost- reducing issue. Successful results from this project would yield significant clinical and public health benefits by way of the potential for increased acceptance among patients, and doing so at considerably lower cost and risks. ***
