The Utility of Timed Segmental Withdrawal During Screening Colonoscopy

The purpose of colonoscopy (colon examination with flexible tube and a camera) is to find early precancerous growth in the colon (polyps) and remove them before they turn into cancer. The doctor performing the procedure will first advance the colonoscope to the end of the colon (cecum) and then he will examine the colon for polyps while he is withdrawing the colonoscope. The period of time that the doctor spent examining the colon called "withdrawal time". Usually doctors will spend at least 6 minutes examining the colon after he reached the cecum. The investigators are proposing that dedicating half of the withdrawal time during colonoscopy in examining the right side of the colon, will increase the detection of polyps in the right side of the colon.