Diagnosing Achalasia

Achalasia is a rare swallowing disorder caused by progressive damage to the nerves that control muscle function in the esophagus, the tube that carries food and liquids to the stomach. NYU Langone gastroenterologists are experienced in diagnosing this condition, which can begin at any age. 

Normally, swallowing triggers an involuntary series of muscle contractions called peristalsis. Over about 8 to 10 seconds, this allows the esophagus to propel food past the lower esophageal sphincter—the ring of muscles that acts as a valve between the esophagus and the stomach—and into the stomach. After food or liquid passes into the stomach, the valve closes to prevent stomach contents from flowing back up into the esophagus. 

Achalasia occurs when nerves are damaged in the smooth muscle portion of the esophagus—which comprises at least the lower two-thirds—as well as to the nerves in the lower esophageal sphincter. As a result, the esophagus is not able to push food down into the stomach and the lower esophageal sphincter cannot relax. This makes it difficult for food and liquids to pass into the stomach, and they often get stuck in the esophagus for a period of time. 

Over time, achalasia causes the lower esophageal sphincter to tighten, making swallowing even more difficult. 

Symptoms and Causes of Achalasia

In addition to having trouble swallowing, many people with achalasia experience symptoms similar to gastroesophageal reflux disease, or GERD, such as chronic heartburn and chest pain. However, these symptoms are the result of food remaining in the esophagus and not from GERD, in which stomach acid flows up into the esophagus. 

Achalasia can also cause frequent hiccupping and difficulty belching. As the condition progresses, achalasia can cause food stuck in the esophagus to regurgitate into the mouth, which can be mistaken for vomiting. 

Doctors don’t fully understand what causes achalasia. Evidence points to genetic factors or to an autoimmune disorder that causes the immune system to mistakenly attack healthy nerve tissue in the esophagus.

Without treatment, achalasia can lead to a severe dilation, or widening, of the esophagus, making it nonfunctional. People with a dilated esophagus may aspirate, or inhale, food and liquids instead of swallowing them, increasing the risk of pneumonia. As it becomes more difficult to swallow, achalasia can lead to dramatic weight loss and malnourishment. 

In addition, achalasia increases the risk of esophageal cancer because retained food and liquids can cause chronic inflammation, irritating the esophagus.

Diagnostic Tests

To diagnose achalasia, our doctors obtain information about your medical history and conduct a physical exam. In addition, they perform an esophageal high-resolution manometry—the gold standard test to diagnose achalasia—as well as other diagnostic tests. 

Each test measures a different aspect of how well the esophagus functions and helps doctors determine the severity of the condition as well as the most effective treatment. 

Chest X-ray

Your doctor may recommend a chest X-ray, which uses electromagnetic radiation to produce images of structures inside the body. He or she analyzes the X-ray image to see if the esophagus is abnormally dilated. 

A chest X-ray alone cannot be used to diagnose achalasia, so it is usually performed in addition to tests that assess swallowing.

Barium Esophagram

A barium esophagram is an imaging test that uses X-rays to obtain detailed pictures of the esophagus during the process of swallowing liquid. In this test, you swallow a contrast agent, or dye, called liquid barium while you assume a variety of positions, including lying down. The liquid barium highlights the esophagus and can reveal a muscle or nerve problem. The test lasts 20 to 30 minutes and takes place in a radiology suite at NYU Langone. 

If the esophagus looks very dilated, or if it appears that the muscles are not coordinated well, you may have achalasia. Your doctor and radiologist often recommend an esophageal high-resolution manometry to confirm the diagnosis.

Upper Endoscopy

Your doctor may recommend an upper endoscopy, a procedure that allows him or her to directly view the esophagus, lower esophageal sphincter, stomach, and the beginning of the small intestine. This procedure can reveal whether the esophagus is dilated, inflamed, or irritated, or if there are any growths or blockages that are causing difficulty swallowing.

An upper endoscopy is performed in the doctor’s office or hospital using sedation. During the procedure, the doctor inserts an endoscope—a flexible tube with a camera at the tip—through the mouth and into the digestive tract.

The doctor may also use the endoscope to perform a biopsy, which involves removing a small piece of tissue from the esophagus or stomach. The tissue sample is examined under a microscope for signs of inflammation, esophageal ulcers caused by undigested food, or cancer. 

An upper endoscopy is usually completed in less than half an hour.

High-Resolution Esophageal Manometry 

Gastroenterologists at NYU Langone recommend esophageal manometry for anyone with symptoms that suggest achalasia. This technique is used to evaluate how well the esophagus is working by measuring changes in pressure within the esophagus while you swallow.  

During manometry, a doctor inserts a narrow, flexible tube called a catheter through the nose or mouth and into the esophagus. Throughout this test, which takes about 10 to 15 minutes, you are asked to take a small sip of water roughly every 30 seconds. The catheter contains small sensors that transmit information about pressure levels and movement in the esophagus to a computer. The doctor views the computer while you swallow.

NYU Langone doctors offer high-resolution esophageal manometry, the most advanced technology available. Using this approach, doctors can identify the specific characteristics of achalasia, which can help them recommend the best treatment.