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Colonoscopy (Lower Endoscopy)

Colonoscopy is a diagnostic procedure that allows the physician to examine the entire length of the large intestine. Colonoscopy can assist in identifying problems with the colon, such as early signs of cancer, inflamed tissue, ulcers, and bleeding. Colonoscopy is also used to screen for colorectal cancer, the second leading cause of cancer-related deaths in the US and the fourth most common cancer in men and women. Patients often don’t feel any symptoms during the early stages of colon cancer, but the colonoscopy can provide your doctor with visual evidence.

During the procedure - as simulated in this animation - a thin, flexible, lighted tube, called a colonoscope, is placed into the rectum and colon. In addition to allowing visualization of the internal colon, the colonoscope enables the physician to irrigate, suction, inject air, and access the bowel with surgical instruments. During a colonoscopy, the physician may remove tissue and/or polyps for further examination and possibly treat any problems that are discovered.

Other related procedures that may be used to assess problems of the colon include abdominal x-ray, computed tomography (CT scan) of the abdomen, abdominal ultrasound, barium enema, and sigmoidoscopy. Please see these procedures for additional information.

How should you prepare for a colonoscopy?

After scheduling an appointment with us, you will be mailed complete instructions on how to prepare for your procedure. Here’s a synopsis of the key things that you should do to prepare:

  1. Call your insurance company and ask if the colonoscopy test is covered for the reason given by your doctor.
  2. Ask your insurance company if you need a referral for the colonoscopy. If they say “yes,” then you MUST get a referral from your primary care physician.
  3. Update your registration by calling 1-866-489-4056.
  4. Make plans for someone to come with you to the hospital.
  5. Five days prior to your procedure, please start a low-fiber diet and do not eat corn, raw vegetables or take fiber supplements (Metamucil®) or iron.
  6. If you take Coumadin®, Plavix®or other blood thinners, please speak with the doctor who prescribed it.
  7. If you are diabetic, please speak with your doctor about how to take your medication in order to prevent low blood sugar.
  8. The day before the colonoscopy you will need to take a laxative preparation. Your medical provider will specify the laxative to be taken on the day prior to the procedure.

What else should I know about a colonoscopy?

To learn more about the anatomy of the colon, screening guidelines, reasons for the procedure, risks of the procedure and what to expect, please review our colonoscopy screening guide.

Contact Us

To request an appointment or more information about the procedure, please contact us at (617) 732-7426.


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