Proctosigmoidoscopy vs. Colonoscopy: Key Differences & What to Expect

A proctosigmoidoscopy and a colonoscopy are invasive procedures than involve an examination of the colon using an endoscope. There are as many differences between the two procedures as there are similarities.

Description

• A proctosigmoidoscopy involves inspection of the lower part of the colon called the sigmoid. Colonoscopy, on the other hand, concerns inspecting the entire colon.

Tools Used

• The tool used is an endoscope, although each procedure uses one designed specifically for the area being examined. A colonoscopy uses a colonoscope, while a proctosigmoidoscopy uses a sigmoidoscope. In both cases, the endoscope is inserted into the rectum.

Purpose

• Both proctosigmoidoscopies and colonoscopies are performed to look for early signs of cancer, determine causes of abnormal bowel functions, or evaluate symptoms. In proctosigmoidoscopies, however, such examinations are restricted to the lower part of the colon.

Polyps

• Polyps---bits of overgrown tissue---can be removed from the sigmoid during a proctosigmoidoscopy and from the entire colon during a colonoscopy.

Other Terms Used

• Proctosigmoidoscopy is also referred to as a sigmoidoscopy.