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Diagnosing Gastroesophageal Reflux Disease

Gastroesophageal reflux disease, or GERD, is a chronic condition in which acid in the stomach—and sometimes nonacidic content—flows into the esophagus, the tube that carries food from the mouth to the stomach. This causes uncomfortable symptoms after eating, such as: heartburn, or a burning sensation in the chest; sore throat; cough; hoarseness; and chest pain. NYU Langone doctors are highly experienced in diagnosing and treating GERD.

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After you swallow, food moves down the esophagus with the help of muscle contractions. Food is then deposited into the stomach, where digestion continues. In people with GERD, the lower esophageal sphincter—a ring of muscles that acts as a valve between the esophagus and stomach—doesn’t function correctly. As a result, stomach acid and food particles are able to reflux, or flow back, into the esophagus.

GERD is very common but its cause is not fully understood. Some people with GERD have problems with the muscles or nerves in the esophagus. Others have a reaction to eating certain foods, such as spicy foods or coffee, that trigger reflux.

GERD may also be caused by a hiatal hernia, a condition in which the upper portion of the stomach bulges into the chest cavity through an opening in the diaphragm—the layer of muscle between the chest and abdomen—called the hiatus. The esophagus passes through the hiatus on its way to the stomach. If the hiatus becomes enlarged, the top of the stomach may push into the chest cavity and prevent the lower esophageal sphincter from closing properly, leading to reflux.


One of the most common symptoms of GERD, heartburn, is a sensation of burning or tightness behind the breastbone. Many people experience occasional heartburn, but in people with GERD, heartburn may occur frequently. Other GERD symptoms may include regurgitation of stomach contents, such as food particles, into the back of the mouth or throat, usually accompanied by an acidic taste; frequent coughing or a hoarse voice; and pain and aching in the chest. Less common symptoms include a feeling of being full, belching, and bloating.

The symptoms of GERD can sometimes feel like the chest pain associated with a heart attack. You should be evaluated by a medical professional immediately if you have any chest pain, so that the cause can be quickly determined and treated.

People experience GERD differently. Some may have only mild or occasional symptoms; in others, symptoms may be more frequent. Over time, if left untreated, GERD can permanently damage the lining of the esophagus. In some people, this can lead to a condition called Barrett’s esophagus, a rare but serious complication of GERD in which precancerous cells appear in the esophageal lining. Other complications include inflammation of the esophagus, or esophagitis; stenosis, or a narrowing of the esophagus, which can affect the ability to swallow foods normally; and worsening cough or asthma symptoms.

It’s normal to have occasional reflux or heartburn, especially after a heavy meal or when lying down after eating. But if you begin to experience reflux persistently or chronically, it is important to seek evaluation by a gastroenterologist—a doctor who specializes in the digestive tract.

Diagnostic Tests

NYU Langone gastroenterologists use the newest and most effective diagnostic tools to determine the cause and severity of GERD. Our gastroenterologists can sometimes diagnose GERD based on your symptoms alone, but they also often perform one or more of the following diagnostic tests. These may help your doctor to determine whether the reflux contains acidic or nonacidic material; whether you have a hiatal hernia; and whether muscle or nerve weakness in the esophagus is causing your symptoms.

These tests also allow your doctor to take a close look at the lining of the esophagus for signs of damage that may indicate esophagitis or Barrett’s esophagus.

Upper Endoscopy

During an upper endoscopy, your gastroenterologist uses a flexible tube with a camera at its tip to examine the esophagus, stomach, and upper part of the small intestine. While you are sedated, your doctor looks for any irritation, inflammation, or other complications to determine the severity of GERD.

If your doctor detects potential abnormalities in the lining of the esophagus, he or she may remove a small piece of esophageal tissue in a procedure known as a biopsy. This tissue is closely examined under a microscope to determine your risk of developing Barrett’s esophagus.

An upper endoscopy is also used to confirm the presence of a hiatal hernia.

Impedance–pH Testing

During an impedance–pH test, your gastroenterologist measures the pH, or acidity, levels in your esophagus during a 24-hour period. The doctor also uses impedance technology to measure how much liquid and air are going up and down your esophagus during this time. This test can determine whether you have acidic or nonacidic GERD, which may influence the treatment your doctor recommends.

During this in-office procedure, the doctor sprays a topical anesthetic into the nose and throat and then inserts a catheter—a thin, flexible tube—through the nose, down the esophagus, and into the stomach. The doctor tapes the catheter to the nose, wraps it around one ear, and then connects it to a small device that can be clipped to your belt or waistband. The device records measurements from the catheter for the next 24 hours. Your doctor also asks you to keep your own written record during this time of any GERD symptoms you experience. You are able to eat and sleep normally during the entire period, and the device does not usually cause discomfort.

The next day, your doctor removes the catheter and compares the episodes of acidic and nonacidic reflux, as recorded by the device, to the time and descriptions of your symptoms, as recorded in your diary. From these results, your doctor can see the amount of reflux produced and whether your symptoms are being caused by acidic or nonacidic reflux.

Bravo pH Monitoring

The Bravo® pH monitoring system allows your doctor to measure the pH, or acidity, levels in your esophagus for 48 to 96 hours.

During this test, a doctor sprays the back of the throat with a topical anesthetic. He or she then gently inserts a small, wireless capsule the size of a gel cap into the throat and attaches it to the inside of the esophagus. You are also fitted with a small recording device that can be worn on your belt or waistband. The capsule and recording device remain in place for 48 to 96 hours, depending on your doctor’s recommendation.

While in place, the capsule detects the pH levels in your esophagus and sends this information to the data recorder. You are asked to keep a diary of your symptoms during the test period. Most people do not feel the capsule while it is in place and continue with their everyday activities.

After the test period, you return to your doctor’s office, where he or she uploads the information from the data recorder to a computer and analyzes it. Your doctor uses this information, along with your recorded symptoms, to determine the severity of GERD and the amount of acid reflux. The capsule does not need to be removed; it detaches on its own and passes naturally through the digestive system.

High-Resolution Esophageal Manometry

Manometry testing assesses the pressure in and movement of the esophagus, so that doctors can determine how well food and liquids move from the mouth to the stomach and whether problems with muscles or nerves in the esophagus may be the cause of GERD.

A doctor places a narrow catheter through the nose and into the esophagus. The catheter contains small sensors that transmit information on pressure and movement in the esophagus. The test takes about 10 to 15 minutes, and your doctor views the information transmitted by the sensors on a computer screen during the procedure.

The test is also helpful for people considering surgery to alleviate GERD; it helps doctors to clarify which procedures may be most beneficial to you.

Barium Swallow Test

A barium swallow test, also called an upper GI series, is an X-ray test to examine the upper digestive tract. During this procedure, you are asked to drink a harmless dose of liquid barium, which temporarily coats the lining of the esophagus, the stomach, and the intestines and is illuminated on X-rays. The barium allows a radiologist to examine these structures as the liquid goes down. A barium swallow is often used along with other tests to give your doctor more information about the esophagus. It can also help in diagnosing a hiatal hernia or any swallowing problems.

Using the results of diagnostic tests, NYU Langone doctors determine the best course of treatment, with the goal of reducing reflux, alleviating discomfort, healing irritation of the esophagus, and preventing progression to a more serious condition, such as Barrett’s esophagus.

Our Research and Education in Gastroesophageal Reflux Disease

Learn more about our research and professional education opportunities.