A sigmoidoscopy is an examination of the rectum and the lower end of the large bowel by means of a flexible tube (endoscope). It is the same as a colonoscopy except that it does not examine all of the colon.

The endoscope has thousands of tiny glass fibres which transmit light to the tip where a tiny camera takes images of the bowel lining and sends them to a video screen. If polyps or other abnormalities are seen, a sample can be taken for examination by the pathologist. 

Why would I need a flexible sigmoidoscopy?

Flexible sigmoidoscopy may be recommended for the colon: 

• To look for causes of blood loss from the bowel

• To assess the extent of inflammation of the colon

• For screening purposes in people without symptoms to look for polyps or colon cancer

• To see if the bowel has been affected by endometriosis

• Following colon surgery to check the bowel and any joins made in it.

Generally, if you are over 50, a full colonoscopy will be more appropriate than the more limited flexible sigmoidoscopy. 

Preparing for a flexible sigmoidoscopy

It is most important that the portion of the rectum and bowel to be examined is cleaned for the examination. The cleaner the bowel the easier and more thorough the examination. 

Cleaning of the bowel is achieved by means of an enema which can be self-administered approximately two hours before the procedure or given at the clinic ½ hour before your appointment with the Specialist. 

What to expect for a flexible sigmoidoscopy

We perform your flexible sigmoidoscopy in a calm, private environment in a procedure room at Intus. The examination is an outpatient procedure which typically takes about 5-10 minutes. It is not usually a painful procedure although some discomfort may be felt when CO2 is introduced into the bowel or as the colonoscope is maneuvered around the corners of the bowel. Sedation or pain relief are not usually necessary. 

The results of the flexible sigmoidoscopy will be reviewed with you at the completion of the procedure and you will receive a written report, a copy of which will also be sent to your general practitioner.

Follow up

If during the procedure abnormalities such as polyps or bowel cancer are seen, then it is likely that the rest of the bowel will need examination. This is usually performed by means of a full colonoscopy which is performed at a later time, after a full bowel preparation. Sometimes, if the enema has produced particularly effective clearance of the colon, it may be appropriate to simply continue the flexible sigmoidoscopy examination to a full colonoscopy at the time. 

If you do have a polyp you are in a high-risk group and are more likely to develop additional polyps. After a polyp is removed you are advised to have your colon examined again at regular intervals.