Digestive Topics : Anorectal Manometry
What is anorectal manometry?
Anorectal manometry (or ARM) is a diagnostic test, not a treatment or intervention. This test utilizes a catheter and a balloon to study the nerves and muscles of the anus and rectum. It tests pressures and sensations in the anus and rectum. The catheter is small, like a rectal thermometer. It is attached to a computer that records the pressures. The result looks like a graph. The balloon contains latex so please inform the doctor if the child is allergic to latex.
Why might a child need anorectal manometry?
This test is done in children with difficult to treat constipation, fecal incontinence (unable to stop stool from leaking), and abnormalities of the anus (anal malformations). The test is used to test the function of the anus and rectum. It tests whether children have normal sensation and are using their muscles correctly to hold and pass stool. It also helps to diagnose a condition called Hirschsprung disease.
How is the anorectal manometry performed?
A rectal examination is done before the test. A catheter with a balloon is passed through the anus to the rectum. The balloon is inflated and pressures and sensations are studied. The child may be asked to squeeze, cough and push the balloon out. The test may last from 15-30 minutes.
What happens before anorectal manometry is performed?
An enema is given at home on the day of the test. A nurse will instruct you about the amount and type of enema to be used. If the test is done without sedation, the child can eat and drink up to the time of the test.
What happens after anorectal manometry is performed?
Immediately following the completion of the test most children are able to return home and resume their daily activity. You may receive the results of the test immediately afterwards or your doctor might need to review the results and contact you within a few days.
What are the risks of anorectal manometry?
This is a very safe test. Rarely, the equipment can fail or there may be bleeding from the rectum as a result of irritation from the balloon or catheter. There are otherwise no adverse effects from the procedure.
What should we watch for after the test?
In most cases your child will experience no ill effects from the test. Some children might develop pain with passing a stool or bleeding from the rectum.
When should we seek medical advice?
You should contact your gastroenterologist if your child has persistent pain or discomfort or passes more than a small amount of blood from the rectum.
- Anorectal manometry is used to study the nerves and muscles of the anus and rectum.
- Children with constipation, leaking of stool from the anus, abnormalities of the anus might undergo this test.
- Anorectal manometry is used to help diagnose Hirschsprung disease.
Photos of anorectal manometry catheters (with attached balloon)
Example of the information collected during anorectal manometry. This graph is interpreted by your child’s pediatric gastroenterologist.
This information from the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) is intended only to provide general information and not as a definitive basis for diagnosis or treatment in any particular case. It is very important that you consult your doctor about your specific condition.