Anorectal Manometry is a test used to evaluate patients with constipation or fecal incontinence. It measures the strength of the anal sphincter muscles, the sensation of the nerves in the rectum, and the reflexes that work together when you have a normal bowel movement.
Normally, when stool enters the rectum, nerves cause the anal sphincter muscles to tighten, allowing you to hold the stool until you are ready to have a bowel movement. When you bear down to have a bowel movement, the same muscles should relax to allow the stool to pass from the rectum. If the sphincter muscles are weak, leakage of stool can occur. In some cases, the sphincter muscles may tighten during a bowel movement, preventing evacuation. This can contribute to constipation.
This test takes approximately 30 minutes and requires no sedation. As you lie comfortably on your left side a small catheter is inserted into your rectum to allow for pressure and sensation measurements. You will be asked to contract or release your rectal muscles during parts of the test. A small balloon on the tip of the catheter will be inflated in order to test your nerve sensation. You may experience a feeling of fullness or distention.
There are no specific risks associated with anorectal manometry. Minor bleeding or discomfort could possibly occur, but are unusual.