Samuel N. Marcus M.D., Ph.D.




For doctors who specialize in the gastrointestinal (GI) tract, examinations are not as easy as those performed on the exterior portions of the body. Not only do we need to get a look deep into your body’s interior recesses and cavities, our examinations involve moving through tight sphincters, soft tissues and persistent valves – which require the use of highly specialized instruments.

A sigmoidoscope, used for sigmoidoscopies, is one of several innovative medical instruments that allows us to get an image of the lowest portion of your intestinal tract, with minimal discomfort on your end.

Sigmoidoscopy Provides Partial Views of the Sigmoid Colon

Your colon is the last section of the large intestine, and it connects directly to your rectum. The last third of the colon is called the sigmoid colon. It forms a curvy S-shape and it about 40 cm in length (just under 16-inches).

When we need to get a good look at the interior of the sigmoid colon, typically for colon cancer screening, there is an option between a colonoscopy or a flexible sigmoidoscopy. Unlike a colonoscopy, which can view the entire interior of the colon, a sigmoidoscopy can only see the left-hand portion of the colon, which has its pros and cons.

Sigmoidoscopies are becoming increasingly popular because they are simpler than a colonoscopy, and work well in combination with a fecal occult blood test (FOBT), preventing the need for all of the prep and sedation required for a colonoscopy.

When is a Sigmoidoscopy Performed?

Typically, a sigmoidoscopy is used to screen for:

  • Colon cancer
  • Polyps
  • Ulcers
  • Abnormal cells

Sometimes, these abnormalities are completely asymptomatic, meaning you won’t have any symptoms. This is especially true when progressive cell abnormalities are in their beginning stages. In other cases, you may experience signs or symptoms of colon disease, such as:

  • Changes in bowel movements
  • Rectal bleeding
  • Inexplicable weight loss
  • Abdominal or rectal pain

If any of these symptoms sound familiar, contact our office and schedule an appointment so we can look into the matter further. It’s much better to be given the “all clear” then to hope something will go away, only to find out later that your latent colon disease has progressed to a point where you require more dramatic treatment. Sooner is always better when it comes to diagnosis and treatment of any medical condition.

If we notice anything unusual during your sigmoidoscopy, we may take small tissue samples so the lab can analyze them. The results will tell us what, if any, treatment or further testing is required.

Preparing For the Procedure

In order to get a good image of your sigmoid colon, we need the tissue to be as clean as possible. To achieve this, we ask that patients:

  1. Enjoy a Clear Liquid Diet. You’ll be asked to follow a clear, liquid diet for one to three days prior to the sigmoidoscopy (cleanses are all the rage these days, right?). Ideas of what you can consume during your 1-3 day cleanse will be clearly outlined in your pre-procedural paperwork.
  2. Use a laxative. To further ensure you colon has evacuated stored contents, you’ll be provided with a laxative. It’s recommended that you stay close to a restroom from this point onward.
  3. Administer an enema. Finally, you’ll be provided with an enema solution (possibly two) that you administer roughly two hours before your scheduled appointment.

After these steps are complete, your sigmoid colon will be the cleanest it has been in years (or at least since your most recent colonoscopy, cleanse or sigmoidoscopy) and we can get an unobstructed view of the tissue inside.

What Does a Sigmoidoscopy Entail?

First, you will be asked to lay on your left-hand side. Because flexible sigmoidoscopes are very thin, and the procedure is so gentle, sedatives are rarely necessary.

The doctor will insert the sigmoidoscope slowly into your rectum, and then continue to feed it along the sigmoid colon. This instrument is equipped with a light and a camera, and a view of your lower-colon is projected on a screen as it moves along its way.

The sigmoidoscope also adds a little air into the colon, which inflates it for easier viewing. This part of the procedure can cause a little bit of discomfort – but shouldn’t be painful.  If necessary, you may need to shift a little this way, or that way, at the doctor’s instruction – to help the scope move forward and to give the doctor a better view.

If there are any visible polyps or growths, the scope is equipped with a small sharp blade and these growths can be removed immediately and painlessly. If the doctor notices any abnormal tissue, a small sample will be taken for biopsy at the lab.

The entire process takes between 10 and 20 minutes, after which, you may experience a little abdominal cramping and/or bloating. This is totally normal. You should be able to drive yourself to and from the office. If any biopsies were required, you will be contacted with their results as soon as we have them.

If you experience pain, dizziness, bloody stool or fever – you should call our office immediately. Fortunately, those types of post-procedure reactions are incredibly rare.

Contact Dr. Marcus to schedule your sigmoidoscopy. Remember that preventative checkups are the best way to catch cancer and other colon diseases before they develop into more serious issues.