Proctoscopy vs Sigmoidoscopy: What You Need to Know About These Common Procedures

Proctoscopy vs Sigmoidoscopy: What You Need to Know About These Common Procedures

Proctoscopy vs Sigmoidoscopy

Sometimes, a doctor needs to check inside your rectum or colon. Two tools for the job are proctoscopes and sigmoidoscopes.

Although these two instruments do share some common characteristics, they differ in both structure and purpose.

Before your next colorectal procedure, here's what you need to know about proctoscopy vs sigmoidoscopy.

All About Proctoscopy

A proctoscope is a long tube that a doctor inserts into your rectum. The tube is rigid, and it does not curve or bend. It is several inches long. Lengths can vary, but proctoscopes are always less than 1 foot long.

Using a proctoscope allows your doctor to see inside your anal canal and rectum, which are the lowest sections of your intestines.

How Proctoscopy Works

You'll need to cleanse your bowels with an enema treatment in preparation for a proctoscopy. Your doctor may have you do this at home before coming in for the procedure, or you might take care of it after arriving at the office.

When it's time for the procedure, you'll need to undress from the waist down. You'll probably receive a gown or a smock to wear. The doctor will have you lie on your side and bring your knees to your chest.

The doctor will slowly and gently insert the proctoscope into your rectum. A light on the end of the device may help your doctor see the tissue. During the procedure, your doctor may use small puffs of air to help open up the passage.

A proctoscopy may feel strange or unusual, but you shouldn't be in pain. Most people describe the feeling as "full" or "crampy." Anesthetic isn't usually required.

If the examination reveals any polyps, the doctor might remove them right away. Tissue samples obtained during the procedure may need to be biopsied.

Finally, the doctor will carefully remove the proctoscope.

When This Procedure Is Used

You're most likely to undergo a proctoscopy if you are experiencing colorectal issues. For example, if you've been experiencing troublesome constipation, diarrhea or bleeding, your doctor might perform this procedure to figure out what the problem is. A practitioner can also perform a proctoscopy to examine or remove hemorrhoids.

A proctoscopy can reveal signs of serious diseases, especially anorectal cancer. If you've been diagnosed with this type of cancer before, you might need regular proctoscopy screenings. However, a proctoscopy cannot detect all cases of colorectal cancer since the instrument does not travel into the colon.

Important Details

  • Another term for "proctoscopy" is "rigid sigmoidoscopy." This can be confusing because it uses a different instrument than the sigmoidoscopy procedure outlined below.
  • Proctoscopy is an outpatient procedure. Your doctor might perform it in the office or in a hospital setting.
  • The whole procedure usually takes no more than 15 minutes.
  • If your proctoscopy reveals polyps or other areas of concern, you may need to follow up with a flexible sigmoidoscopy or a colonoscopy.

All About Sigmoidoscopy

A sigmoidoscope is a long, flexible instrument for insertion into your rectum and part of your colon. The tube of a sigmoidoscope is typically thinner than that of a proctoscope, and there's a light and a camera at the end. The tool may measure over 2 feet in length.

Your doctor can explore farther with a sigmoidoscope than with a proctoscope. In addition to showing the rectal issue, this instrument can also travel partway into the large intestine to explore the curved portion near its end; this segment is known as the sigmoid colon. However, a sigmoidoscope is not long enough to view the upper or right portions of the colon.

How Sigmoidoscopy Works

As with proctoscopy, you'll need to prepare your bowels before having a sigmoidoscopy. For a sigmoidoscopy, this may be a more involved process that involves a special diet and laxatives in addition to an enema.

There are many other similarities to a proctoscopy. You'll undress and lie on your side. The doctor will gently insert the device and use air to expand the tissue. Although you may feel some discomfort, this procedure isn't usually painful, so you probably won't require anesthesia.

The doctor can remove polyps or other abnormalities during the sigmoidoscopy. Biopsy samples may be sent off for testing.

After the doctor removes the tube, you can go home and resume normal activities right away.

To view an animation of a flexible sigmoidoscopy and learn more about the procedure, watch the following video:

When This Procedure Is Used

The primary purpose of a sigmoidoscopy is to detect colon cancer. It can serve as a screening even for those who are experiencing no symptoms of cancer or other diseases. Because this test is less invasive than a colonoscopy, you may undergo sigmoidoscopies more frequently.

Of course, you may also have a sigmoidoscopy in response to colorectal concerns. For example, if you are experiencing pain, bleeding or frequent diarrhea, your doctor might recommend this procedure.

Important Details

  • To distinguish this procedure from a proctoscopy, the name "flexible sigmoidoscopy" is often used.
  • As with a proctoscopy, this is an outpatient procedure that can be performed in an office or hospital setting.
  • The procedure is usually about 15 minutes long.
  • Beginning at age 50, it's a good idea to get a sigmoidoscopy every five years. Those with elevated risk factors may need to do it earlier or more often.

Now that you know the differences involved with proctoscopy vs sigmoidoscopy, you'll be prepared for your next colorectal procedure.

  • Both instruments slide into your anal opening to give your doctor a close look at portions of your large intestine.
  • Rigid proctoscopes focus on the anal canal and rectum, and flexible sigmoidoscopes can also view the sigmoid colon.
  • These tools are useful for both diagnostic and screening purposes.

Consult your doctor to learn more about which procedure is right for your current medical needs.

Brian Chandler

Brian Chandler