Oesophageal Manometry

About your oesophagus

The oesophagus is a tube that connects your mouth with your stomach. The walls of the oesophagus are very muscular, and contract (squeeze) rhythmically when you swallow to help move food and liquids into your stomach. This action is called peristalsis.

In some people these contractions do not work properly. In such cases, a test known as oesophageal manometry may be needed to help diagnose the problem. Difficulty swallowing may be experienced if the contractions of your oesophagus are too weak or irregular, while chest pain may result if the contractions are too strong.

What is oesophageal manometry?
Oesophageal manometry is a diagnostic test that is sometimes referred to as an oesophageal function or oesophageal motility study. It is used to check how well the muscles of the oesophagus are working, as well as to measure the strength of the lower oesophageal sphincter or ‘valve’ that prevents the backward flow of food from the stomach into the oesophagus.

How is the test done?
A thin, soft tube is passed through your nose or mouth and into the oesophagus. The tube has pressure sensors along its wall and, when in place, can measure the pressure that is produced by the oesophagus muscles when relaxing or squeezing.

You will be asked to take small sips of water so that the pressures during the swallowing action can be recorded and analysed using a computer.

Anaesthesia is generally not required for the procedure, although anaesthetic spray may, if necessary, be used on the throat to minimise discomfort.

Once all the information has been gathered the tube is removed and the test is completed. The whole procedure generally takes about an hour, although a complete analysis of the test results may take several days.

Why is the test done?
This test may be undertaken if your doctor suspects that you are suffering from one of a number of conditions related to the function of the oesophagus. One such condition is called achalasia, where the normal rhythmic contractions of the oesophagus are lacking and also the valve to the stomach fails to relax, causing food to build up in the oesophagus.

Another use of oesophageal manometry is in diagnosing and evaluating difficulty in swallowing where other investigations have not led to a diagnosis.

What are the risks and benefits of this test?
You may experience a mild gagging sensation when the tube is swallowed, but once in place there are generally no problems. After the test you may have a mild sore throat. There may also be a risk for people with swallowing difficulties of inhaling saliva or gastric acid into the lungs instead of swallowing it in the normal way.

However, the benefits are that it provides information on the muscular function of your oesophagus that cannot be obtained by any other technique. This can then allow either the development of a specific treatment programme, or reassurance if the results are normal.