Proctoscopy is a procedure used to diagnose problems with your rectum and anus. The rectum is the end of your large intestine (colon). The anus is the opening of the rectum.

The device used to perform this procedure is a hollow tube called a proctoscope. A light and lens on the device lets your doctor examine the inside of your rectum.

This procedure is also called rigid sigmoidoscopy. It’s different from a flexible sigmoidoscopy, which is another type of procedure used to diagnose problems with the lower portion of the colon.

You might have a proctoscopy to:

  • diagnose a disease in your rectum or anus, including cancer
  • find the cause of bleeding from the rectum
  • diagnose hemorrhoids
  • remove a sample of tissue for testing, called a biopsy
  • find and remove polyps and other abnormal growths
  • monitor rectal cancer after surgery or other treatments

At least a week before your procedure, tell your doctor about any medications you take. Include all:

  • prescription drugs
  • over-the-counter medicines
  • herbal supplements and vitamins

You might need to stop taking some or all of these a few days before your test, especially if you take medications that thin your blood. Follow your doctor’s instructions.

Cleaning out your rectum before the test can make the area easier for your doctor to examine the area.

If your doctor wants you to cleanse your bowel, you’ll give yourself an enema or take a laxative the day before the procedure. An enema uses a salt-water solution to flush out the contents of your rectum. Your doctor will give you instructions on how to do this.

A proctoscopy can be done at a hospital or outpatient clinic. You shouldn’t need any anesthesia, unless you want it to feel more comfortable.

You’ll lie on your side with your knees bent.

First, your doctor will insert a gloved, lubricated finger into your rectum. This is called a digital exam. It’s done to check for any blockages or sore areas.

Then the doctor will insert the proctoscope into your anus. Air will be pushed into your colon to help your doctor view the area.

The doctor might remove a sample of tissue during the procedure. This is called a biopsy. It’s done using very small tools passed up through the proctoscope.

You may feel some cramping and fullness during this test, along with an urge to empty your bowels. But the procedure shouldn’t be painful.

The whole test takes about 10 minutes. Afterward, the doctor will remove the proctoscope. Then you should be able to go home.

There are few risks from a proctoscopy. You may bleed a little bit for a few days after the procedure.

Other, less common risks include:

  • infection
  • belly pain
  • a tear in the rectum (this is rare)

You may have some discomfort in your rectum and anus right after the procedure. You might also have some light bleeding from your rectum or blood in your bowel movements for a few days afterward. This is normal, especially if you had a biopsy.

You should be able to go back to your regular activities and eat your usual diet after a proctoscopy.

During your recovery, call your doctor if you have any of these symptoms:

  • a fever of 100.4°F (38°C) or higher
  • a large amount of blood in your stool
  • bleeding that lasts for more than a few days after your procedure
  • severe pain in your abdomen
  • a hard, swollen belly

You might get your results right away. The doctor who performs your proctoscopy can let you know what the test found.

If you had a biopsy, the tissue sample will be sent to a lab for testing. It may take a few days or weeks to get the results. Your doctor will call you or ask you to come in to discuss your biopsy results.

Depending on what the test finds, you might need more tests or treatments.

Flexible sigmoidoscopy is another test used to diagnose diseases of the colon and rectum, including colorectal cancer. The sigmoidoscope is a thin, flexible tube with a video camera on the end.

The main difference between these two tests is the length of the devices used to perform them.

  • A proctoscope measures about 10 inches (25.4 centimeters) long, so it only reaches the bottom part of your lower intestine.
  • The scope used in a flexible sigmoidoscopy is about 27 inches (68.6 centimeters) long, so it allows your doctor to view a much greater area of your large intestine.

A colonoscopy is yet another test doctors use to view the inside of the colon and rectum. It can screen for colon cancer and diagnose the cause of problems like rectal bleeding or belly pain.

A colonoscopy is performed with a thin, flexible tube called a colonoscope. It’s the longest of all three scopes, reaching the whole length of the colon.

The extended length allows doctors to diagnose problems throughout the whole colon, instead of just in the rectum and anus, like proctoscopy.

Proctoscopy can be a somewhat unpleasant, but sometimes necessary way to diagnose problems with the lower part of your intestine and anus. If your doctor recommends this procedure, ask about its benefits and risks compared to other scopes like colonoscopy and flexible sigmoidoscopy.

It’s important to have this test if you need it. Getting diagnosed early for certain conditions can lead to quicker treatment and better outcomes, which makes a few minutes of mild discomfort more than worth it.