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A flexible sigmoidoscopy is an endoscopic procedure that allows your doctor to examine the rectum and lower colon. A sigmoidoscope is a specialized endoscope, a thin, flexible lighted tube with a camera at the tip that your doctor uses to visualize the area.
The procedure is similar to a colonoscopy, but the sigmoidoscope does not reach as far as the colonoscope. Flexible sigmoidoscopy takes approximately 10 to 20 minutes and may be performed in your doctor’s office.
A: Position of the sigmoidoscope in the colon;
B: endoscopic view; C: detail of the colonoscope tip
Flexible Sigmoidoscopy: Why It’s Performed
Flexible sigmoidoscopy is a well-tolerated procedure that causes minimal discomfort. Your doctor may recommend it in order to evaluate:
- Abdominal pain
- Rectal bleeding
- Change in bowel habits
- Chronic diarrhea
- Other intestinal problems
Your doctor may also use flexible sigmoidoscopy to screen for colon cancer.
Flexible Sigmoidoscopy: What to Expect
In order to ensure a safe and thorough procedure, you will need to follow a clear liquid diet and have an enema prior to the procedure. This way your digestive tract is clear and your doctor has good visibility. Your doctor will give you specific instructions on how to prepare, including which prescription medications are safe to take.
During a flexible sigmoidoscopy, you remain awake and lie on your left side. Usually, no sedative is necessary. Your doctor will:
- Insert the lubricated sigmoidoscope through the rectum and into the anus and large intestine.
- Introduce some air into your colon to improve visibility; you may experience some cramping or pressure when this happens.
- Examine the images on a nearby monitor.
- Possibly insert biopsy forceps through the scope in order to remove a small sample of tissue for further analysis.
Patient positioning and room set-up for sigmoidoscopy and colonoscopy
After the procedure, your doctor will discuss the findings with you. You can go home the same day and return to your regular activities right away.