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Understanding Flexible Sigmoidoscopy

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What is flexible sigmoidoscopy? 

Flexible sigmoidoscopy lets your doctor examine the lining of the rectum and a portion of the colon (large intestine) by inserting a flexible tube about the thickness of your finger into the anus and slowly advancing it into the rectum and lower part of the colon.


Flexible sigmoidoscopy is a test that uses a flexible, narrow tube with a light and tiny camera on one end, called a sigmoidoscope or scope, to look inside the rectum, the sigmoid colon, and sometimes the descending colon. In most cases, a patient does not need anesthesia. However, conscious sedation medications are often provided at the time of the procedure.

What preparation is required?

Your doctor will tell you what cleansing routine to use. In general, preparation consists of one or two enemas prior to the procedure but could include laxatives or dietary modifications as well. However, in some circumstances your doctor might advise you to forgo any special preparation. Because the rectum and lower colon must be completely empty for the procedure to be accurate, it's important to follow your doctor's instructions carefully.


Should I continue my current medications?

Most medications can be continued as usual. Inform your doctor about medications that you're taking - particularly aspirin products or anticoagulants (blood thinners such as warfarin or heparin), or clopidogrel, as well as any allergies you have to meds.


What can I expect during flexible sigmoidoscopy?

Flexible sigmoidoscopy is usually well-tolerated. You might experience a feeling of pressure, bloating or cramping during the procedure. You will lie on your side while your doctor advances the sigmoidoscope through the rectum and colon. As your doctor withdraws the instrument, your doctor will carefully examine the lining of the intestine.


During a flexible sigmoidoscopy, the patient will lie on a table or stretcher while the health care provider inserts the sigmoidoscope into the patient's anus and slowly guides it through the rectum, the sigmoid colon, and sometimes the descending colon. The scope inflates the large intestine with air to give the health care provider a better view. The camera sends a video image of the intestinal lining to a monitor, allowing the health care provider to examine the tissues lining the sigmoid colon and rectum. The health care provider may ask the patient to move several times and adjust the scope for better viewing. Once the scope reaches the end of the sigmoid colon, the health care provider slowly withdraws it while examining the lining of the colon and rectum again. The health care provider will look for signs of bowel diseases and conditions e.g., irritated and swollen tissue, ulcers, and polyps. If the health care provider suspects ulcerative colitis, he or she will biopsy the patient's colon and rectum.

What if the flexible sigmoidoscopy finds something abnormal?

If your doctor sees an area that needs further evaluation, your doctor might take a biopsy (tissue sample) to be analyzed. Obtaining a biopsy does not cause any pain or discomfort. Biopsies are used to identify many conditions, and your doctor might order one even if he or she doesn't suspect cancer. If your doctor finds polyps, he or she might take a biopsy of them as well. Polyps, which are growths from the lining of the colon, vary in size and types. Polyps known as "hyperplastic" might not require removal, but benign polyps known as "adenomas" have a small risk of becoming cancerous. Your doctor will likely ask you to have a colonoscopy (a complete examination of the colon) to remove any large polyps or any small adenomas.


What happens after a flexible sigmoidoscopy?

Your doctor will explain the results to you when the procedure is done. You might feel bloating or some mild cramping because of the air that was passed into the colon during the examination. This will disappear quickly when you pass gas. You should be able to resume normal activities after leaving your doctor's office or the hospital, assuming you did not receive any sedative medication.


What are possible complications of flexible sigmoidoscopy?

Flexible sigmoidoscopy and biopsy are safe when performed by doctors who are specially trained and experienced in these endoscopic procedures. Complications are rare, but it's important for you to recognize early signs of possible complications. Contact your doctor if you notice severe abdominal pain, fevers, chills, or rectal bleeding. Note - bleeding can occur several days post-exam.

What is flexible sigmoidoscopy?
what prep is required?
should I continue current med?
what can I expect during procedur?
what if result show abnormalities
what happens after procedure?
possible complications?
flexible sigmoidoscopy
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