During a colonoscopy, a flexible, thin lighted tube called a colonoscope is inserted into the rectum. This allows the physician to look inside the entire large intestine (also known as the colon). This procedure may be performed to see things such as inflamed tissue, abnormal growths and ulcers. It allows the physician to look for early signs of cancer in the colon and rectum, or to look for causes of unexplained changes in bowel habits, or to evaluate symptoms like abdominal pain, rectal bleeding, and weight loss.
