Anal Manometry

You’ve been referred for anorectal manometry, which will help your doctor, evaluate or treat your condition. This pamphlet is meant to give you a basic understanding of the procedure – how it is performed, how it can help, and what side effects you might experience. It can’t answer all of your questions, since a lot depends on the individual patient and the doctor. Please ask your doctor about anything you don’t understand.

What Is Anorectal Manometry?

During anorectal manometry a small, flexible tube, about the size of a thermometer, with a balloon at the end is inserted into the rectum. The catheter is connected to a machine that measures the pressure. During the test, the small balloon attached to the catheter may be inflated in the rectum. This test measures the pressures of the anal sphincter muscles, the sensation in the rectum, and the neural reflexes that are needed for normal bowel movements.

Why Is Anorectal Manometry Done?

Anorectal manometry is a test performed to evaluate patients with fecal incontinence or constipation:

  1. Fecal incontinence – There are many causes of fecal incontinence. Weak anal sphincter muscles or poor sensation in the rectum can contribute to fecal incontinence. If these abnormalities are present, they can be treated. Biofeedback techniques using anal manometry and special exercises of the pelvic floor muscles can strengthen the muscles and improve sensation.
  2. Constipation – There are many causes of constipation. Some involve sluggish movement through the whole colon, whereas others involve the anal sphincter muscles. In some patients with constipation, the anal sphincter muscles do not relax appropriately when bearing down or pushing to have a bowel movement. This abnormal muscle function may cause a functional type of obstruction. Muscles that do not relax with bearing down can be retrained with biofeedback techniques using anal manometry.

How Should I Prepare For Anorectal Manometry?

Your doctor will instruct you as to whether or not you need to take any laxatives or enemas prior to the examination. Tell your doctor in advance of the procedure about all medications that you’re taking and about any allergies you have to medication. He or she will tell you whether or not you can continue to take your medication as usual before the examination.

What Can I Expect During Anorectal Manometry?

The test takes approximately 30 minutes. You will be asked to change into a hospital gown. A technician or nurse will explain the procedure to you and answer any questions you may have. The patient then lies on his or her left side. The catheter is then inserted into the rectum and slowly withdrawn. The nurse or technician may also ask the person to squeeze, relax, and push at various times. The anal sphincter muscle pressures are measured during each of these maneuvers. To squeeze, the patient tightens the sphincter muscles as if trying to prevent anything from coming out. To push or beardown, the patient strains down as if trying to have a bowel movement. Two other tests may be done: first, an anal sphincter electromyography (EMG), a test to evaluate the nerve supply to the anal muscle; second, measurement of the time it takes to expel a balloon from the rectum. After the examination, you may drive yourself home and go about your normal activities.

What Are The Possible Complications Of Anorectal Manometry?

Anorectal manometry is a safe, low risk procedure and is unlikely to cause any pain.

Complications are rare: it is possible that a perforation (tearing) or bleeding of the rectum could occur. Equipment failure is a remote possibility. If you are allergic to latex, you should inform the nurse/technician before the test so that a latex free balloon can be used.

Additional Questions?

If you have any questions about your need for anorectal manometry, alternative approaches to your problem, the cost of the procedure, methods of billing or insurance coverage, do not hesitate to speak to your doctor or doctor’s office staff about it.