What is flexible sigmoidoscopy?

Healthcare providers may suggest a flexible sigmoidoscopy for colorectal cancer screening. A flexible sigmoidoscopy is recommended for people at risk for colorectal cancer every five years. Doctors use a flexible, lighted tube (sigmoidoscope) to look at the interior walls of the rectum and part of the colon.

A flexible sigmoidoscopy is a procedure that allows for a close check of the lining of the rectum and part of the colon. It checks the lower one-third of the colon, while colonoscopy views the entire colon.

Medicine for relaxation is not usually needed for a flexible sigmoidoscopy. During the test, if an area needs to be looked at more closely, a sample of the colon lining will be taken (biopsy) for testing. Polyps are not removed with this test. The test takes 10 to 15 minutes. You will be told when you can eat and be active.

Flexible sigmoidoscopy lets your doctor examine the lining of the rectum and a portion of the colon (large intestine) by inserting a flexible tube about the thickness of your finger into the anus and slowly advancing it into the rectum and lower part of the colon.

A flexible sigmoidoscopy is a test in which the doctor looks at part of the colon and rectum with a sigmoidoscope—a flexible, lighted tube about the thickness of a finger with a small video camera on the end. It is inserted through the rectum and into the lower part of the colon. Images from the scope are viewed on a display monitor.

Using the sigmoidoscope, your doctor can view the inside of the rectum and part of the colon to detect (and possibly remove) any abnormality. Because the sigmoidoscope is only 60 centimeters (about 2 feet) long, the doctor is able to see the entire rectum but less than half of the colon with this procedure.

Sigmoidoscopy is a diagnosic procedure that allows the physician to examine the lower part of the large intestine—the rectum and bottom two feet of the colon. It is helpful in identifying the causes of diarrhea, abdominal pain, constipation, abnormal growths and bleeding. A thin, flexible tube is inserted into the large intestine through the rectum. The tube has a tiny light and camera at its end that is connected to a TV monitor, allowing the doctor a good view of this part of the large intestine. If necessary, the doctor may take a small tissue sample (biopsy) from the lining of the intestine to look at later under a microscope.

A sigmoidoscopy typically takes 5 to 10 minutes, requires only an enema for preparation, and can be done without sedation. Patients may experience some cramping and discomfort during this procedure.

Physicians may also couple a sigmoidoscopy with another procedure known as a double-contrast barium enema. With this, barium is infused into the rectum via an enema tube and an x-ray is taken of the area. The barium helps produce a clearer, more detailed x-ray of the area.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.