Learning Materials
Colonoscopy
Colonoscopy lets the physician look inside your entire large intestine, from the lowest part, the rectum, all the way up through the colon to the lower end of the small intestine. It is the single best test for detection of tumors or cancer, but it is not perfect. It is also used to diagnose the causes of unexplained changes in bowel habits or other intestinal symptoms. Colonoscopy enables the physician to see inflamed tissue, abnormal growths, ulcers, and bleeding.
For the procedure, you will lie on your left side on the examining table. A needle for intravenous (IV) medicines will be placed in your arm vein before the procedure. An anesthesiologist will then administer an intravenous sedative to keep you comfortable and to help you relax during the exam.
Once you are sedated, the physician will insert a flexible, lighted tube into your rectum and slowly guide it into your colon. The tube is called a colonoscope. The scope transmits an image of the inside of the colon, so the physician can carefully examine the lining of the colon. The scope bends, so the physician can move it around the curves of your colon. The scope also puffs air into your colon, which inflates the colon and helps the physician see better. Most of this air is then removed at the end of the procedure.
If anything abnormal is seen in your colon, like a polyp or inflamed tissue, the physician can remove all or part of it using tiny instruments passed through the scope. That tissue (biopsy) is then sent to a lab for testing. If there is bleeding in the colon, the physician can pass a heater probe, or bicep probe, or can inject special medicines through the scope and use it to stop the bleeding.
Colonoscopy with biopsy or removal of polyps is associated with a low risk of complications when performed by a physician who has been specially trained and is experienced in the procedure. However, there are risks associated with any endoscopic examination, such as: a medication reaction, lack of awareness lasting a few hours, or swelling of an arm vein following medication injection. More serious complications may also occur. These complications include but are not limited to bleeding after a biopsy or removal of an intestinal growth, infection, or a perforation of the intestine which may require immediate surgery. Hospitalization, surgery and/or colostomy may also be required for any unforeseen complication. Overall, such complications are very uncommon.
Colonoscopy takes 15 to 30 minutes. The sedative medicine should keep you from feeling much discomfort during the exam. You will need to remain at the colonoscopy facility for a short time until the sedative wears off.