Flexible sigmoidoscopy

Flexible sigmoidoscopy is a procedure used to see inside the sigmoid colon and rectum. It can detect inflamed tissue, abnormal growths, and ulcers. The procedure is used to look for early signs of cancer and can help doctors diagnose unexplained changes in bowel habits, abdominal pain and bleeding from the back passage.

What are the sigmoid colon and rectum?

The sigmoid colon is the last one-third of the colon. The colon comprises three main parts: the ascending colon, the transverse colon, and the sigmoid colon—sometimes called the descending colon. The colon absorbs nutrients and water and forms stool.

The rectum is about 6 inches long and connects the sigmoid colon to the anus. Stool leaves the body through the anus.

How is a flexible sigmoidoscopy different from a colonoscopy?

Flexible sigmoidoscopy enables the doctor to see only the sigmoid colon, whereas colonoscopy allows the doctor to see the entire colon. Colonoscopy is the preferred screening method for cancers or polyps of the colon and rectum. However, to prepare for and perform a flexible sigmoidoscopy requires less time and preparation.