The purpose of high-resolution esophageal manometry is to measure the pressures in your esophagus when you are resting and when you swallow. These pressures will tell us if your esophagus is working normally. The most common uses for the test are to:
- Diagnose esophageal motility disorders (e.g., spasms and achalasia)
- Prepare for and follow-up anti-reflux surgery
- Evaluate results of medical and surgical treatment
- Determine lower esophageal sphincter location before a 24-hour pH study
- Evaluate non-cardiac chest pain
- Evaluate non-mechanical dysphagia (difficulty swallowing)
- Evaluate rumination syndrome
To prepare for the study:
- Do not eat or drink after midnight if you will have the test in the morning. If the test is scheduled in the afternoon, you can have a light breakfast 4 hours before the test. (If you are diabetic, please talk to your primary care doctor).
- You may take scheduled medications at least two hours prior to the study with small sips of water.
- You may brush your teeth.
How is esophageal manometry performed?
- Esophageal manometry takes about 45 minutes. The technician will verify that you have not eaten anything within 4 hours of the study. At the start of the test, you will be sitting upright. One nostril is anesthetized with a numbing lubricant. A thin flexible plastic tube approximately one-eighth inch in diameter is passed through the anesthetized nostril, down the back of the throat, and into the esophagus as you swallow. With further swallowing, the tube is passed down into the stomach. There may be some gagging during some of the passage, but it is easily controlled by following instructions. Occasionally, the tube is passed through the mouth and not the nose.
- With the tube inside the esophagus, you will lie down on your back. After a short rest to allow the pressures to equilibrate, the test will begin. The pressures generated by the esophageal muscle will be measured when the muscle is at rest and during swallows. During the test, the technician usually asks the patient to swallow on command with some liquid (called a wet swallow). Multiple swallows are tested to allow measurement of the lower esophageal sphincter (the barrier to reflux), the esophagus (the swallowing tube), and the upper esophageal sphincter (in the throat). Pressure recordings are made throughout the study. Then you will sit up and repeat the same swallow sequence depending on the protocol. Once the test finished, the tube is withdrawn.
- Patients can usually resume regular activity, eating, and medicines immediately after the test.
What are the side effects of esophageal manometry?
- Although esophageal manometry may be slightly uncomfortable, the procedure is not really painful because the nostril through which the tube is inserted is anesthetized. Once the tube is in place, patients talk and breathe normally. The side effects of esophageal manometry are minor and include mild sore throat, nosebleed, and, uncommonly, sinus problems due to irritation and blockage of the ducts leading from the sinuses and into the nose. Occasionally, during insertion, the tube may enter the larynx (voice box) and cause choking. When this happens, the problem usually is recognized immediately, and the tube is rapidly removed. Care must be used in passing the tube in patients who are unable to easily swallow on command because without a swallow to relax the upper esophageal sphincter the tube often doesn’t enter the esophagus but instead enters the larynx.
When is esophageal manometry used?
- Esophageal manometry is used primarily in several situations. The first is to evaluate the cause of reflux of stomach acid and contents back into the esophagus (gastroesophageal reflux disease or GERD). Symptoms of GERD include heartburn and regurgitation. The second is to determine the cause of problems with swallowing food, such as food or liquids getting stuck in the chest after swallowing. The third is to evaluate patients with chest pain that may be coming from the esophagus rather than the heart. Finally, the test may be needed to correctly place an acid sensing probe (pH probe) in the esophagus (see patient information sheet on esophageal pH monitoring).
How is esophageal manometry used?
- Esophageal manometry can diagnose several esophageal conditions that result in food sticking after it is swallowed. For example, achalasia is a condition in which the muscle of the lower esophageal sphincter does not relax with each swallow to allow the swallowed food into the stomach. As a result, food is trapped within the esophagus. Abnormal function of the muscle of the body of the esophagus also may result in food sticking. For instance, there may be failure to develop the wave of muscular contraction to help propel the food down the esophagus (as can occur in patients with scleroderma). The abnormal functioning of the esophageal muscle also may cause episodes of severe chest pain that can mimic heart pain (angina). Such pain may occur if the esophageal muscle goes into spasm (esophageal spasm) or contracts too strongly. In either case, esophageal manometry can identify the muscular abnormality.
- Esophageal manometry is also used to evaluate patients who might have gastroesophageal reflux disease (GERD). Manometry often can identify weakness in the lower esophageal sphincter – the muscle that prevents stomach acid and contents from refluxing back up into the esophagus. The procedure will also help localize the lower esophageal sphincter which would help if esophageal pH monitoring is performed.