Gastroenterology - High Resolution Ano-Rectal Manometry Study

Introduction

Your doctor may want you to have Ano-rectal manometry studies (reading of anal sphincter muscle pressures) because you may be having difficulty in controlling your bowel.

Weakness of the sphincter muscles (the rings of muscle around the anus) can give rise to difficulty in holding back the bowel contents, thus leading to faecal incontinence (inability to hold gas and stool in the rectum).

On the other hand, inability of the sphincter muscle to relax properly (when you try to open your bowels) can cause constipation, as it then creates a barrier stopping complete emptying of the rectum (back passage).

The rectum is the last bit of large bowel in which stool collects before it is expelled.

The manometry test involves passing a small catheter through your back passage into the rectum and recording the pressures inside.

This will provide information on the strength of the anal sphincter muscles and its ability to contract and relax.

The test takes about one and a half hours and is done in the gastro intestinal (GI) physiology unit on the endoscopy suite.

Procedure

In the unit you will be met by the nurse or GI Physiologist who will check your personal details with you.

You will then be asked to complete the relevant sections of the history proforma.

You will then be taken into the procedure room. You will be asked to remove your lower clothes and will be given a gown to wear.  You will then be seen either by a doctor or GI Physiologist who will go through your medical history in detail. He/ she will then explain the procedure to you and after that you will be asked to sign a consent form.

You will then be asked to lie on your left side on a couch.

The doctor or the GI Physiologist will then do a per-rectal examination with the finger. He will also check for the peri-anal sensation and ano-cutaneous reflex (superficial reflexes).

After that a small 5mm thick probe called high resolution ano- rectal manometry catheter containing several sensors on them is passed into the rectum and is then taped in place.

You will be asked to squeeze and bear down several times during the test. You will also be asked to blow a party balloon during the test. Relevant measurements are then taken.

A small balloon will then be introduced through the back passage into the rectum. The balloon will be slowly inflated with air in steadily increasing volumes.

You will be asked to report when you feel the first rectal sensation of the balloon followed by urge to open the bowels, desperate urge and and finally a strong sensation of discomfort/pain.
 
Finally, the balloon inside the rectum will be filled with a small volume of warm water, following which you will be asked to sit on a commode and expel it. Once the test is complete the doctor/GI Physiologist will analyse the tracing and report it back to the referring clinician with relevant recommendations.

The result will also be explained to you on the same day.

Depending upon the result of the test you will be brought back for a course of biofeedback therapy if deemed appropriate.

No sedation is used so you may drive home.

No special preparation is required but it is recommended that you empty your bowel prior to the test. No specific medication to empty the bowel, such as laxatives are required for the test.

Please continue with any regular medications if any has been prescribed for you by a doctor.

If you are diabetic please continue with your tablet or injections provided you take your regular breakfast and lunch.

Benefits

This test will tell whether your sphincter muscles are weak or not in case of faecal incontinence, or in the case of constipation, whether the sphincter muscle appropriately relaxes or not during bowel emptying.

Risks

There are no risks attached to the procedure.

Alternatives

No other tests are available to study the strength of the sphincter muscles.

If you need any further information or clarification on any aspects of the test please contact the GI Physiologist, GI Physiology Unit/Endoscopy Unit, Rochdale Infirmary on:

01706 517547
01706 517550
01706 517859