Flexible Sigmoidoscopy

An exam used to evaluate the lower part of the large intestine or colon is called flexible sigmoidoscopy. A thin and flexible tube or sigmoidoscope will be inserted into the rectum during this exam.

Your doctor can view the inside of the rectum and most of the sigmoid colon which is the last two feet or 61 centimeters of the large intestine because it has a tiny video camera at the tip of the tube.

Sometimes, biopsies can be taken through the scope but this test does not allow the doctor to see the entire colon, meaning doctors cannot detect cancer or polyps farther into the colon.

Your doctor may suggest a flexible sigmoidoscopy exam for the following reasons:

• screen for colon cancer – your doctor may suggest this exam every five years if you are age 50 or older and you have no colon cancer risk factors other than age
• investigate intestinal signs and symptoms – this test can help your doctor check the possible cause of rectal bleeding, abdominal pain, chronic diarrhea, changes in bowel habits and other intestinal problems

Consult your doctor if you want to have other exams to visualize your whole colon.

A flexible sigmoidoscopy exam poses a few risks but complications that are rare may include:

• a tear in the rectum or colon wall
• bleeding from the area where the tissue sample was taken

In order to prepare for the flexible sigmoidoscopy exam, you will need to empty your colon, because any residue in your colon may obscure the view of your rectum or colon during the exam.

Your doctor may ask you to:

Follow a special diet a day before the exam such as limit the drinks to clear the liquid (plain water, broth, tea, carbonated beverages, coffee without cream or milk) or you may not be able to drink or eat by midnight the night before the exam.

Take a laxative the night before the exam which comes in liquid form or pill.

Adjust your medications such as adjust your dosages or stop taking the medication temporarily at least a week before the exam especially if you are taking supplements or medications that contain iron for diabetes or aspirin and blood thinners.

Use an enema kit the night before or a few hours before the exam to empty your colon.

Read on to learn more about what to expect before, during, and after your flexible sigmoidoscopy exam.

You will be asked to wear a gown and lie down on your side usually with your knees drawn toward your chest then he will insert the sigmoidoscope in your rectum.

This device contains a light and a channel which allows your doctor to pump air into your colon because this air will inflate the colon for your doctor to have a better view of the colon lining.

You may feel abdominal cramping or the urge to move your bowels when the scope is moved. Your doctor can study the inside of your colon by the images from the tiny video camera.

He can also do biopsies by inserting instruments through the channel. Pain medications and sedation are not necessary and this exam usually takes about 15 minutes.

Your doctor would suggest a full colonoscopy to check your whole colon if he found a polyp. You may have a mild abdominal pain or you may feel bloated or pass gas for a few hours after the exam.

You should do some walking for the relief of discomfort. There may be a small blood in your first bowel but consult your doctor if you continue to pass blood, have a fever of 100 F (37.8 C) or have a persistent abdominal pain.

You and your doctor will discuss the flexible sigmoidoscopy results together.

If it is a negative result it means that there are no abnormalities in the colon but your doctor may suggest waiting for five years to repeat the exam if you are at average risk of colon cancer.

If it is a positive result it means that the doctor found an abnormal tissue or polyps in the colon.

You may need additional testing such as colonoscopy to check the abnormalities more thoroughly and to check for other abnormalities.

Your doctor may suggest repeating the flexible sigmoidoscopy exam or another screening test if he is concerned about the quality of the view.