A flexible sigmoidoscopy allows your doctor to see the inside of the rectum and sigmoid colon (the last one-third of the colon), and detect abnormal growths, ulcers or inflammation. It's recommended to look for early signs of cancer, diagnose unexplained bowel changes, abdominal pain, weight loss and bleeding.

How Do You Prepare for a Flexible Sigmoidoscopy?

If the only requirement is an empty rectum, you will be asked to administer an enema at home a couple of hours before the procedure in preparation. If it's necessary to empty the entire gastrointestinal tract, you will be on a liquid diet the day before the test and be required to thoroughly cleanse the colon via prescription laxatives and/or bowel cleanses via oral solutions.

What Can You Expect With a Flexible Sigmoidoscopy?

Once you are transferred to a procedure room, you will be asked to lie on your left side. The doctor may administer a sedative or light anesthetic. A sigmoidoscope is inserted into the anus, guided through the rectum and into the sigmoid colon. If you are not under anesthesia, the doctor may occasionally ask you to change position in order to manipulate the scope for more effective observation. The doctor may also remove small pieces of tissue for biopsy and remove polyps. The entire procedure takes approximately 10-20 minutes.

What Happens Next?

Upon waking in a recovery bay, you won't have any recollection of the procedure and might feel a little 'foggy' from the anesthesia/sedation. Since the procedure often requires the doctor to inflate the colon with air, you may experience mild stomach cramps and the need to pass gas. It's mandatory that a companion be available, not only to drive you home but to discuss initial findings with your physician. Preliminary results may be discussed, and if necessary, a follow-up appointment with any physician on Memorial Hermann's multi-disciplinary team may be scheduled.

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