Colonoscopy is a procedure that lets your doctor look inside your entire large intestine. It uses an instrument called a colonoscope, or scope for short. Scopes have a tiny camera attached to a long, thin tube. The procedure lets your doctor see things such as inflamed tissue, abnormal growths, and ulcers.
Your doctor may recommend a colonoscopy for a number of reasons:
To look for causes of unexplained changes in bowel habits
To evaluate symptoms like abdominal pain, rectal bleeding, and weight loss
Your doctor can also remove polyps from your colon during a colonoscopy.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases
Definition (NCI)
Examination of the inside of the colon using a colonoscope, inserted into the rectum. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.
Definition (MSH)
Endoscopic examination, therapy or surgery of the luminal surface of the colon.
Definition (NCI)
Endoscopic examination of the luminal surface of the colon.