Anorectal Manometry Balloon Expulsion Test

What Is Anorectal Manometry?

Anorectal manometry measures:

• The strength and coordination of the anal sphincter muscles
• Sensation in the rectum
• Reflexes necessary for normal bowel movements

The results help clinicians determine if the muscles are too tight, too loose, or not functioning in sync, guiding targeted treatment for bowel disorders

Procedure Details

• Preparation: Patients typically undress from the waist down or change into a hospital gown. The procedure is explained, and any questions are answered by the healthcare provider.
• Positioning: The patient lies on their left side with knees drawn up (fetal position).
• Insertion: A small, flexible, lubricated tube (catheter) with a deflated balloon at the end is gently inserted into the rectum. The catheter is connected to a machine that records pressure data.
• Testing: The balloon may be inflated at various depths inside the rectum to assess muscle function and reflex pathways. Patients may be asked to squeeze, relax, and push as if having a bowel movement, allowing measurement of muscle pressures during each maneuver.
• Duration: The test typically takes about 30 minutes and is well-tolerated. Afterward, patients can resume normal activities.

Results and Clinical Value

• Diagnosis: The test identifies abnormalities in muscle strength, coordination, and sensation, which are common in conditions like chronic constipation, fecal incontinence, and pelvic floor dysfunction.
• Treatment Planning: Results guide therapies such as biofeedback, pelvic floor retraining, or surgical interventions.