Understanding Fiberoptic Evaluation of Swallowing (FEES)

Front view of man showing respiratory and upper digestive anatomy.A fiberoptic evaluation of swallowing (FEES) test is used to see if you have dysphagia. Dysphagia is when you have trouble swallowing. It can lead to serious problems, such as lung infection. During the FEES test, a thin, flexible tool called an endoscope is thread through your nose and down your throat. Parts of your throat are viewed as you swallow. The test is done by a speech-language pathologist (SLP). An SLP has special training in the areas of speech, language, voice, and swallowing.

Dysphagia and aspiration

When you swallow food, it passes from your mouth down into your throat (pharynx). From there, the food moves down through a long tube (esophagus) and into your stomach. This journey is made possible by a series of actions from the muscles in these areas. If you have dysphagia, the muscles don’t work properly. You may not be able to swallow normally.

The pharynx is also part of the system that brings air into your lungs. When you breathe, air enters your mouth and moves into the pharynx. The air then goes down into your main airway (trachea) and into your lungs. A flap of tissue called the epiglottis sits over the top of the trachea. This flap blocks food and drink from going down into the trachea when you swallow. Aspiration is when something enters the airway or lungs by accident. It may be food, liquid, or some other material. This can cause serious health problems, such as pneumonia. Aspiration can happen when a person has dysphagia.

Why a FEES test is done

A FEES test can help find out if you are having problems with any part of the swallowing process. An SLP will often first see how well you are swallowing with other simple tests. A FEES test is then done to get more information about your swallowing. If you have dysphagia, aspiration is always a risk. So dysphagia needs to be identified quickly. Many health problems can lead to dysphagia. Some examples are:

  • Stroke

  • Head or neck cancer

  • Head injury

  • Major dental problems

  • Conditions that lessen saliva (such as Sjogren’s syndrome)

  • Mouth sores

  • Parkinson’s disease or other neurologic conditions

  • Muscular dystrophies

  • Blockage in the esophagus (such as from cancer)

You may need a FEES test if you have symptoms such as:

  • Food sticking in your throat

  • Difficulty or pain while swallowing

  • Certain breathing problems

You may need the test even if you don’t have any symptoms of dysphagia. You may still be at risk for aspiration.

How a FEES test is done

An anesthetic will be sprayed in your nose and throat. This is so you don’t feel the endoscope. The SLP quickly puts the endoscope through your nose and down into your throat (pharynx). The endoscope sits above your epiglottis for most of the viewing. It then can be moved down after each swallow so the vocal folds may be seen. The endoscope allows your SLP to see parts of your larynx, pharynx, and trachea on a video screen. The endoscope may puff small amounts of air into your throat. This is to test the nerves in your throat. You may swallow small amounts of food or liquid during the test. These will be dyed so they can be seen on the screen.

Risks of a FEES test

All procedures have some risks. The SLP will work to lessen these risks. The risks of a FEES test include:

  • Nosebleed

  • Discomfort

  • Gagging or vomiting

  • Brief closing of your airway (laryngospasm)

  • A small amount of aspiration