A fiberoptic endoscopic evaluation of swallowing (FEES) test is a procedure used to assess how well you swallow. During the procedure, a speech-language pathologist (SLP) or an ear, nose and throat doctor (ENT or otolaryngologist) passes a thin, flexible instrument, called a laryngoscope, through your nose. Then they can view parts of your throat (oropharynx and larynx) as you swallow.

When you swallow food or liquid, it passes through your mouth and down through parts of your throat called the pharynx and larynx. From here, the food or liquid passes through a long tube (esophagus) before entering your stomach. This movement requires a series of actions from the muscles in these areas. It also requires coordination with the muscles of breathing, since breathing pauses during a swallow.

When you breathe, air passes through your pharynx and larynx, too. It then travels down through a long tube called the trachea before it reaches your lungs. There is a small piece of tissue called the epiglottis that acts like a flap and covers your trachea when you swallow food or drink. This is so food and fluids don't go into your trachea and lungs.

A FEES test can help assess if you are having any problems with any part of this process. A FEES test uses a flexible tube called a laryngoscope, sometimes called an endoscope. This instrument has a tiny camera and light attached to it. Before the FEES test, you may have an anesthetic sprayed in your nose or throat to help numb the area so you don't feel the tube being gently inserted. Your doctor will pass the laryngoscope through your nose and into your pharynx. It sits above your epiglottis for most of the viewing and then can be moved down after each swallow so the vocal folds may be seen. The laryngoscope allows your doctor to see parts of your larynx, oropharynx, and trachea on a video screen.

The FEES test has two basic parts. During the first phase, the structure of the oropharynx and larynx is usually observed. The doctor will watch how well you swallow saliva before any food. The second part of the FEES test is when food is introduced. Here your swallowing will be assessed with different textures and sizes of food and liquid. Food color to dye the food and liquid may be used so it's easier to view on screen. You may need to change positions or try different types of foods as your throat and swallowing function is evaluated.

You may need this test if you have trouble swallowing (dysphagia). With dysphagia, something goes wrong with the muscular coordination needed for normal swallowing. Dysphagia can lead to food or fluid going into the airways or lungs (aspiration) by accident. This can lead to pneumonia and other problems, such as choking, malnutrition, and dehydration. Dysphagia in adults can also result in a loss of interest in food and social isolation. Because of this, it's important to promptly identify and treat dysphagia if you have it.

A FEES test can help your doctor identify what parts of your throat and mouth might not be working well. The FEES test can also show if there are certain foods or liquids you need to stay away from, or if certain positions can help you swallow more safely. The FEES test can also show if you are aspirating.

You might need a FEES test if you have any symptoms of dysphagia, like a sense of food sticking in your mouth or pain with swallowing. You also might need a FEES test if you have a medical condition that puts you at high risk of dysphagia, even if you don't have symptoms. Some people with dysphagia don't have any symptoms. For example, if you have had a stroke, someone will need to check to see if you have dysphagia. This might require getting a FEES test. Other conditions that might cause dysphagia include:

• Head and neck cancer
• Head injury
• Conditions that lead to decreased saliva, such as Sjögren syndrome
• Muscular dystrophies
• Obstruction in the esophagus, such as from cancer
• Progressive neurologic disorders, such as amyotrophic lateral sclerosis (ALS), Parkinson disease (PD), and multiple sclerosis (MS); and Alzheimer disease and related dementias

In many cases, an SLP will first assess your swallowing with some simple tests. You may need to swallow and move your mouth in certain ways. The SLP checks if certain kinds of substances seem to give you difficulty. Based on the results of this swallowing exam, your SLP or ENT doctor may want to schedule a FEES test to get more information about the cause of your possible dysphagia.

A similar test is the modified barium swallow test (MBS). This uses X-rays to view your swallowing. One of the advantages of the FEES test over the MBS is that the FEES test doesn't use radiation. And unlike the MBS, a FEES test may be done in an office or clinic instead of a hospital. You may also have a videofluoroscopic swallowing study or an esophagogastroduodenoscopy to assess your throat and how you swallow.

All procedures have some risks. The risks of FEES include:

• Nosebleed
• Discomfort
• Gagging or vomiting
• Brief closure of your airway (laryngospasm)
• Aspiration (usually only a small amount)

The SLP will work to reduce these risks. Your own risks may vary according to your age, your general health, and the reason for your procedure. Talk with the SLP to find out what risks may apply to you.

Until your FEES test, your doctors may want to put you on a special diet to help prevent aspiration. Only eat and drink what is on the approved list. The doctors will instruct you if there is anything else you need to do to prepare.

Tell the medical team about all prescription and over-the-counter medicines you take. This includes any medicine that thins the blood. You may need to stop taking some medicines before the procedure. Also tell the medical team if you have had any surgery to your neck, throat, or nose.

If you are a patient in the hospital, the FEES test may be done in your hospital room. Or, you may go to an ENT office or clinic to have the test. Your SLP may do the procedure alone, or with the help of an ENT doctor.

Your ENT doctor and SLP can give you an idea of what to expect during your test. The procedure often takes around 20 minutes. Each person's experience may vary. In general this is what you can expect:

• During the test, you'll be seated and awake. An anesthetic will be sprayed in your nose and throat. This is so you don't feel the laryngoscope, sometimes called an endoscope.
• Your ENT doctor or SLP quickly inserts the endoscope through your nose and down into your throat (pharynx). You might feel mild discomfort during the procedure. Some people also experience a sense of tightness or a gagging sensation. The anesthetic can reduce this.
• The ENT doctor or SLP watches the video screen to see how well you are swallowing and if you are aspirating. Your ENT doctor or SLP will look at a number of factors. These include how well secretions are swallowed, how well breathing and swallowing occur together, and how well the airway closes off. They will also be able to see if there are any abnormal structural problems.
• The laryngoscope may puff small amounts of air into your throat, testing your sensations.
• You may also take small amounts of food or liquid. These will be dyed so they can be seen on the screen.
• At the end of the procedure, the laryngoscope will be gently pulled out from your pharynx and nose.

In many cases, you will be told the results of your test right away. You might even watch a video of the test. If you had the test done in an ENT doctor's office or clinic, you will likely be able to drive yourself home after your exam. You will probably be able to resume your normal activities right away.

If your FEES test shows that you have problems swallowing, your health care team will work together to develop a treatment plan for you. This may include modifying the types of foods you eat. For example, you may need to stay away from liquids of a certain thickness. Communicate with your team so that suggested treatment plans include foods that reflect your food preparation abilities, culture, and financial resources. You may need to make changes in your positioning while you eat. And you may need to learn certain methods for swallowing better.

It's important to work closely with your health care team. Carefully following their instructions and keeping all follow-up appointments can help you reduce your risk of complications, such as pneumonia from aspiration.

Before you agree to the test or procedure make sure you know:

• The name of the test or procedure
• The reason you are having the test or procedure
• What results to expect and what they mean
• The risks and benefits of the test or procedure
• What the possible side effects or complications are
• When and where you are to have the test or procedure
• Who will do the test or procedure and what that person's qualifications are
• What would happen if you did not have the test or procedure
• Any alternative tests or procedures to think about
• When and how you will get the results
• Who to call after the test or procedure if you have questions or problems
• How much you will have to pay for the test or procedure