What Is It?
Colonoscopy is an examination of your complete colon, or large intestine. Colonoscopy is similar to another type of exam called sigmoidoscopy, which looks at only the last part of the colon. To perform colonoscopy, your doctor uses an instrument called a colonoscope, which is a flexible viewing tube with lenses, a small TV camera and a light on one end. Through bundles of flexible glass fibers (fiber-optic technology) and a small video computer chip, the colonoscope scans the inside of your colon and transmits images to a video screen.
During colonoscopy, your doctor can check your colon for abnormal growths called polyps, sites of bleeding and for other conditions such as colitis. The procedure may take up to an hour and is done in a special endoscopy suite or the outpatient area of a hospital. Although the colonoscope is lubricated and bends easily, you will be lightly sedated to minimize any discomfort.
What It's Used For
Colonoscopy is used to look at the lining of your colon. This makes it useful in detecting colon cancer, polyps, inflammation and other problems of the gastrointestinal tract. To screen routinely for colon cancer, your doctor may recommend colonoscopy every 7 to 10 years. Colonoscopy should begin earlier in people with a high risk of colorectal cancer due to a family history of colorectal cancer, chronic inflammatory bowel disease or certain hereditary syndromes, including familial adenomatous polyposis. Regular colonoscopy at more frequent intervals also is recommended for anyone who has already had either a cancerous growth or precancerous polyp removed from the bowel.