A Colonoscopy is an examination of the bowel (large intestine or colon) using a flexible telescope called a colonoscope. The colonoscopy allows for a variety of operations to be carried out such as tissue samples (biopsies), removal of polyps and the stopping of bleeding. An alternative method of examination of the large bowel is by x-ray or CT Scan. Colonoscopy has the advantage over x-ray tests of generally being more accurate for detecting diseases of the bowel and also allows for biopsies to be taken and polyps removed.
Patients have a colonoscopy for several reasons. For example, there may be symptoms such as bleeding, altered bowel habit or pain suggesting a disorder of the bowel. Alternatively, it may be performed as a screening test for cancer or polyps in people with or without symptoms, or as a follow up test after a positive FOBT.