Esophageal manometry


Esophageal manometry is a test to measure the pressure inside the lower part of the esophagus.

Alternative Names

Esophageal motility studies; Esophageal function studies

How the test is performed

During esophageal manometry, a thin, pressure-sensitive tube is passed through your mouth or nose and into your stomach. Once in place, the tube is pulled slowly back into your esophagus.

When the tube is in your esophagus, you will be asked to swallow. The pressure of the muscle contractions will be measured along several sections of the tube.

While the tube is in place, other studies of your esophagus may be done. The tube is removed after the tests are completed. The test takes about 1 hour.

How to prepare for the test

You should not have anything to eat or drink for 8 hours before the test.

How the test will feel

You may have a gagging sensation and some discomfort when the tube is put into place.

Why the test is performed

When you swallow, muscles in your esophagus contract to help push food toward your stomach. Valves, or sphincters, inside the esophagus open to let food and liquid through, and then close to prevent food, fluids, and gastric acid from moving backward. The sphincter at the bottom of the esophagus is called the lower esophageal sphincter or LES.

The purpose of esophageal manometry is to see if the esophagus is contracting and relaxing properly. The test helps diagnose any swallowing problems. Your health care provider may request that this test be performed if you have symptoms of:

  • Acid reflux (heartburn or nausea after eating)
  • Problems swallowing (feeling like food is stuck behind the breast bone)

Normal Values

The LES pressure and muscle contractions are normal when you swallow.

What abnormal results mean

Abnormal results may indicate:

  • -- a problem with the esophagus that affects its ability to move food toward the stomachAchalasia
  • A weak low esophageal sphincter, which causes acid reflux
  • -- abnormal contractions of the esophagus muscles that do not move food effectively to the stomachDiffuse esophageal spasm

What the risks are

The tube in the esophagus may cause increased salivation , which raises your risk for aspiration . This can lead to lung injury or aspiration pneumonia .

In general, people with swallowing difficulty are at higher risk for aspiration.

Special considerations


Wilson JF. In the clinic: gastroesophageal reflux disease. . 2008;149:ITC2-1-ITC2-15.

Richter JE, Friedenberg FK. Gastroesophageal reflux disease. In: Feldman M, Friedman LS, Brandt LJ, eds. . 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 43.

Encyclopedia content is provided as information only and not intended to replace the advice and instruction from your personal physician.