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What is a Sigmoidoscopy?

Sigmoidoscopy is a procedure in which a doctor looks in your large intestine. A length of flexible tube connected to a fiberoptic camera is used. A light is transmitted through the scope to the tip by a bundle of light fibers. The doctor uses this light to look at your intestine through an eyepiece or video screen.

  • Your doctor may do this very safe procedure for several reasons.
  • Three findings are possible from this procedure.
    • You are healthy, and no other studies are needed. (Even though the sigmoidoscopy is the most important technique in the evaluation of colon cancer, a very small percentage of people with normal sigmoidoscopy findings may later be found to have colon cancer.)
    • A diagnosis of your particular disease is made.
    • You may need additional testing, consultation, therapy, or follow-up.
  • Several leading medical groups recommend routine screening of men and women aged 50 years and older for colon cancer and benign (harmless) polyps every 3-5 years. Younger people may require this procedure if they have close relatives with colon cancer.
  • A similar screening procedure is known as a colonoscopy. The basic difference is that the tube goes farther up the colon with a colonoscopy.
Last Reviewed 11/20/2017
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