Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get StartedDefinition
By Mayo Clinic staffA colonoscopy is an exam used to detect changes or abnormalities in the large intestine (colon) and rectum. Colonoscopy is generally considered the gold standard for colon cancer screening.
During a colonoscopy, a long, flexible tube (colonoscope) is inserted into the rectum. A tiny video camera at the tip of the tube allows the doctor to view the inside of the entire colon. If necessary, polyps or other types of abnormal tissue can be removed through the scope during a colonoscopy. Tissue samples (biopsies) can be taken during a colonoscopy as well.
- Corbett JV. Laboratory Tests and Diagnostic Procedures With Nursing Diagnoses. 7th ed. Upper Saddle River, N.J.: Pearson/Prentice Hall; 2008:745.
- Schilling McCann JA, ed. Diagnostic Tests. Philadelphia, Pa.: Lippincott Williams & Wilkins; 2007.
- Colonoscopy. National Digestive Diseases Information Clearinghouse. http://digestive.niddk.nih.gov/ddiseases/pubs/colonoscopy. Accessed March 18, 2009.
- Fletcher RH. Screening strategies in patients at average risk for colorectal cancer. http://www.uptodate.com/home/index.html. Accessed March 18, 2009.
- Levin B, et al. Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: A joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology. Gastroenterology. 2008;134:1570.
- Weinberg DS. In the clinic: Colorectal cancer screening. Annals of Internal Medicine. 2008;148:ITC2-1.