Sigmoidoscopy

What is sigmoidoscopy?

Sigmoidoscopy is an exam of the lower part of the bowel (large intestine) with a slim, flexible, lighted tube called a sigmoidoscope. The scope is passed into the rectum and slowly advanced into the part of the bowel called the sigmoid colon. The scope lets your provider look inside about one half of the colon.

When is it used?

Sigmoidoscopy is a way to screen for cancer of the colon or rectum. This type of screening may be done when you have no symptoms but are at risk for this type of cancer. It may also be done to help diagnose diarrhea, bleeding, pain, or inflammation in the rectum.

An alternative to this procedure is a colonoscopy. A colonoscope is longer and allows examination of all of the colon.

How do I prepare for the exam?

Follow your healthcare provider's instructions about not smoking before and after the procedure.

If you need a minor pain reliever in the week before the procedure, choose acetaminophen rather than aspirin, ibuprofen, or naproxen. This helps avoid extra bleeding if you need a biopsy. If you are taking daily aspirin for a medical condition, ask your provider if you need to stop taking it before the procedure.

Your provider may ask you to restrict your diet the day before the procedure. You may be asked to take a liquid laxative or to give yourself an enema at home just before the procedure. Or you may be given an enema at your provider's office 30 minutes to 1 hour before the procedure. For an enema, fluid is forced into your rectum to cause a bowel movement.

What happens during the exam?

The procedure is done in your healthcare provider's office. You will not need anesthesia. Usually you lie down on your left side with your knees bent and drawn up to your stomach. Before the sigmoidoscope is inserted into your rectum, the tip of the scope is lubricated to cause less discomfort. Your healthcare provider may use the scope to put air inside the bowel to see better. Your provider can view the images of the colon on a TV monitor.

If your provider sees anything abnormal during the exam, he or she may take small samples of tissue through the scope for lab tests. If a polyp or cancer is found, your provider will recommend a colonoscopy. This will allow your provider to look at all of the colon. A biopsy can be done during the colonoscopy to remove polyps and abnormal tissue. A colonoscopy is usually done at different facility at a later time.

The sigmoidoscopy exam takes about 10 to 20 minutes.

What happens after the exam?

After the test, it is normal to feel some bloating or cramping. You will also need to pass gas to get rid of the extra air that was pumped into the bowel during the test. Walking may help relieve the discomfort.

Unless your provider tells you otherwise, there are no special measures to take after the procedure.

What are the benefits of this procedure?

This procedure helps your healthcare provider diagnose problems in the colon. For some of these problems, such as cancer, treatment is more effective when the problem is found early. If polyps are found and removed, cancer of the colon may be prevented.

What are the risks associated with this procedure?

Risks include:

• damage to the colon (perforation) by the sigmoidoscope
• bleeding or infection inside the colon
• some pain or swelling in your lower abdomen if air was put into your bowel during the procedure (this will last until your body passes the extra air shortly after the procedure)

When should I call my healthcare provider?

Call your provider right away if:

• You have severe abdominal pain after the procedure.
• You have a fever.
• Pain or symptoms you had earlier get worse.

Call during office hours if:

• You have questions about the procedure or its result.
• You want to make another appointment.