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WHAT IS A COLONOSCOPY?

Colonoscopy is a procedure that allows the doctor to visually examine the entire lining of the colon and rectum using a colonoscope (a long flexible tube about the thickness of a finger). The colonoscope is inserted into the rectum and gradually advanced through the colon. The doctor is able to
carefully examine the lining of the rectum and diagnose colon and rectal problems, perform biopsies, and remove polyps.

WHO SHOULD HAVE A COLONOSCOPY?
The doctor may recommend a colonoscopy to:
• Screen the colon at age 50 or earlier if there is a family history of colon cancer.
• Examine and possibly remove polyps or tumors located by a barium enema exam.
• Monitor patients with a past history of colon polyps or cancer, or with a strong family history of colon cancer.
• Examine patients who test positive for blood in the stool.
• Check inflammatory bowel disease (colitis).
• Check unexplained abdominal symptoms or change in bowel habits.
• Identify cause of unexplained bleeding.

HOW IS A COLONOSCOPY PERFORMED?
A colonoscopy is done in an outpatient setting. Patients take an oral preparation to cleanse the bowel the day before the procedure. The colonoscope is inserted into the rectum and gradually advanced through the colon. The doctor may inject
medicine to relax the patient and help ease any discomfort. Colonoscopy is done under sedation not anesthesia. The entire procedure usually takes less than an hour. The patient usually may resume normal activities the following day.

WHEN IS A BIOPSY DONE?
If the doctor sees an area in the bowel that needs further evaluation, a biopsy forceps can be passed through the colonoscope to take a sample of tissue (biopsy). This sample will be sent to the hospital lab. Biopsies are taken for many reasons and do not necessarily mean that cancer is suspected.

WHAT IS A POLYPECTOMY?
Polypectomy is the removal of a polyp. During the course of the examination, a polyp may be found. Polyps are abnormal growths of tissue which vary in size from a tiny dot to several inches. If the doctor feels that removal of the polyp is indicated, a wire loop or snare will be passed through the colonoscope and the polyp removed from the intestinal wall using an electrical current. If additional polyps are detected, they may be
removed as well. Polyp removal is not painful.

Polyps are usually removed because they can cause bleeding, contain cancer, or be a precursor of cancer. Although the majority of polyps are benign (non-cancerous), a small percentage may contain an area of cancer in them or may develop into cancer. Removal of colon polyps therefore
is an important means of prevention of colon cancer, a leading form of cancer in the United States.
Click here for more information on colon polyps.

WHAT ARE THE RISKS OF COLONOSCOPY?
• Bleeding
• Perforation