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Patient Education: Diseases Conditions Treatments & Procedures

Colonoscopy

Introduction

A procedure to carefully examine the entire lining of the rectum and colon, using a colonoscope, a flexible tube with a light on the end.  In preparation for the procedure, the patient is directed on how to clear the bowel of all solid matter over a period of one to three days. 

For the procedure, patients are often given sedation intravenously.  During the colonoscopy, abnormalities can either be totally removed (in the case of polyps, which are small growths on the lining), or if a larger abnormality is found, a sample (called an endoscopy biopsy) can be taken during this procedure.  These tissue samples are then sent to a pathologist who examines them under a microscope to determine the diagnosis.