Esophageal manometry is a test that is performed by inserting a special catheter that measures pressure in the esophagus and the LES. It is not used for diagnosing GERD per se, but it is a useful test to do on patients prior to GERD surgery. It is also used for patients who have noncardiac chest pain. It may provide important information to physicians who are trying to decide whether surgery is the right course of action. Not only that, the type of GERD surgery that is performed may be influenced by the results of this test.
For example, for patients with normal pressure in esophageal contractions, fundoplication surgery would involve wrapping the stomach all around the esophagus (360 degrees). On the other hand, if contraction pressures are weak, then the surgeon may prefer to wrap the stomach around only partially so that weak contractions can push the food through the lower esophageal sphincter.