The esophagus is a tubular organ leading from the mouth to the stomach, both ends of which have a muscular valve called a sphincter. The upper esophageal sphincter lies in the pharynx area (throat), and the lower esophageal sphincter is at the junction between the esophagus and stomach (behind the lower part of the sternum). During an esophageal manometry, the function of both sphincters, as well as the function of the tubular esophagus, is tested.
An esophageal manometry is often performed when patients complain of difficulty swallowing and tests show no blockage. These tests can include upper endoscopy and barium swallow. Esophageal manometry is the test of choice when achalasia is suspected. Esophageal manometry is also useful in documenting abnormalities in the lower esophageal sphincter and contraction abnormalities in the body of the esophagus in patients with refractory gastroesophageal reflux disease (GERD).
Some patients have other disorders that lead to problems with esophageal contraction. For example, many patients with scleroderma have abnormal esophageal manometry tests. Manometry tests are done in patients with severe GERD when surgery is being contemplated for repair of a hiatal hernia (fundoplication). Esophageal spasms can cause severe chest pain that mimics heart disease. These spasms can be detected by appropriate manometry testing using various stimuli such as medications or even balloon distention within the esophagus.
Preparation for Manometry
Patients are usually asked to take nothing by mouth for at least eight hours. The procedure is explained. Cooperation is essential.
The thin plastic tube is passed via the nose or the mouth into the esophagus after the application of local anesthetic. This is usually easy with minimal coughing or gagging. The tube is then advanced into the stomach. By observing the pressure recordings on a computer screen, the lower esophageal sphincter, the esophageal body and upper esophageal sphincter can be located.
The patient remains in a comfortable lying position. Recordings are taken from different locations within the esophagus. The patient will be asked to breath in and out, and to make a number of swallows, to see how the esophagus reacts. Failure of the lower esophageal sphincter to relax is an indication of achalasia.
The waves of contraction, which occur after each swallow, can be seen on a computer screen. These measurements indicate whether the contractions are of normal strength, speed and direction. After testing is complete the tube is gently removed. The test usually is completed within 10–15 minutes. The traces recorded on the computer screen are printed out and analyzed. Patients can return to their usual activities. Sometimes another test is done in conjunction with manometry.