Virtual colonoscopy.

Abstract

Colorectal cancer is the second leading cause of cancer deaths in the United States. Most colorectal cancers start as polyps- benign (non-cancerous) growths on the inner wall of the rectum and colon. Polyps develop slowly over many years. Currently, doctors recommend that everyone be screened for colon cancer starting at age 50. A new emergent technology to screen for colorectal cancer is virtual colonoscopy which has been introduced in the medical field. Virtual colonoscopy, also known as CT colonography, uses an x-ray machine linked to a computer to generate unique 2-D and 3-D images of the colon and rectum that can be manipulated for better viewing angles and stored for later study. The procedure does call for the insertion of a rectal tube to push air into the colon for a better view. No sedation is required, but as with traditional colonoscopy, patients must take laxatives and fast 24 hours prior to screening. Conventional colonoscopy is the visual exam of the upper parts of the lower intestine using a flexible instrument about 3 feet long that is inserted through the anus into the colon. Patients are sedated during the procedure. Until now conventional colonoscopy was the primary screening tool for colorectal cancer because according to different studies that were made by experienced gastroenterologists, conventional colonoscopy has a high sensitivity and specificity to detect colon polyps. This research study compares virtual colonoscopy with conventional colonoscopy and different aspects such as sensitivity and specificity of both modalities are tackled. In conjunction to this advantages and disadvantages, patient acceptability and risks, cost effectiveness and availability of both modalities are discussed. Virtual colonoscopy has done major advances in the medical field as a screening tool for colorectal cancer but it is still considered less effective than conventional colonoscopy. Until now, conventional colonoscopy has all the necessary requirements to be and remain the unique primary screening tool for colorectal cancer.