Sigmoidoscopy Health Article

Definition

Sigmoidoscopy is an internal examination of the lower large bowel (colon), using an instrument called a sigmoidoscope.

Alternative Names

Proctoscopy; Proctosigmoidoscopy

How the test is performed

During the test, you are positioned on your left side with your knees drawn up toward your chest. A gastroenterologist or surgeon will perform the test. First, the doctor does a digital rectal exam by gently inserting a gloved and lubricated finger into the rectum to check for blockage and to dilate (gently enlarge) the anus.

Next, the sigmoidoscope -- a hollow tube with a camera on the end -- is inserted into the rectum. Air is introduced into the colon to expand the area and help the doctor see better. The air may cause the urge to have a bowel movement.

The sigmoidoscope is advanced, usually as far up as the sigmoid colon or descending colon. Then, as the scope is slowly removed, the lining of the bowel is carefully examined. The hollow channel in the center of the scope allows for the passage of forceps for taking biopsies or for other instruments for therapy.

How to prepare for the test

You must sign an informed consent form. You will wear a hospital gown.

On the morning of the procedure, eat a light breakfast and then use a cleansing enema about 1 hour before the sigmoidoscopy.

Infants and children:

The preparation you can provide for this test depends on your child's age, previous experiences, and level of trust. For general information regarding how you can prepare your child, see the following topics:

• Infant test or procedure preparation (birth to 1 year)
• Toddler test or procedure preparation (1 to 3 years)
• Preschooler test or procedure preparation (3 to 6 years)
• Schoolage test or procedure preparation (6 to 12 years)
• Adolescent test or procedure preparation (12 to 18 years)