Anorectal manometry

A diagnostic test to evaluate the function of the muscles in the rectum and anus

Anorectal Manometry

Diagram of the anorectal region

Anorectal manometry is a diagnostic procedure used to evaluate the function of the muscles in the rectum and anus. This test is particularly useful in assessing conditions related to defecation disorders, such as fecal incontinence and constipation.

Purpose

The primary purpose of anorectal manometry is to measure the pressures of the anal sphincter muscles, the sensation in the rectum, and the neural reflexes that are necessary for normal bowel movements. It helps in diagnosing conditions like Hirschsprung's disease, anismus, and other anorectal disorders.

Procedure

During the procedure, a small, flexible tube with a balloon at the end is inserted into the anus and rectum. The balloon is inflated, and the pressures exerted by the muscles are recorded. The test typically lasts about 30 minutes and is performed on an outpatient basis.

Indications

Anorectal manometry is indicated for patients experiencing:

• Chronic constipation
• Fecal incontinence
• Difficulty in passing stool
• Suspected Hirschsprung's disease

Interpretation

The results of anorectal manometry provide information about:

• Anal sphincter pressure
• Rectal sensation
• Rectoanal inhibitory reflex
• Coordination of the muscles during defecation

Abnormal results may indicate dysfunction in the anal sphincter muscles or nerve supply, which can guide further treatment options.

Related pages

• Fecal incontinence
• Constipation
• Hirschsprung's disease
• Defecation