Linda here: Bonnie Pfeiffer is a speech pathologist who has CMT. This item was prompted by the following question:
"Why is it when I went to have my throat looked at they couldn't find anything wrong with my swallowing? I know there is a problem but how do I prove it to my doctor? Is there a test?"

The answers to these questions are complex at best. As most of us are aware, research in the area of degenerative neurologic disease processes has been limited – particularly concerning CMT. There is even less literature available about associated swallowing disorders. Many studies have looked at swallowing in populations of individuals having a variety of neurologic diseases. Others have focused on groups of homogenous patients without regard to the degree of neurologic involvement in individuals. This makes for difficulty in identifying typical swallowing dysfunctions or in predicting progression.

There is, however, a great deal known about the types of swallowing problems symptomatic of degenerative diseases similar to CMT, tests available to diagnose specific impairments, and techniques for remediation or compensation.

Disordered Swallowing
Normal swallowing consists of three phases: oral, pharyngeal, and esophageal. During the oral phase of swallowing, food must be chewed, moved on to the tongue, gathered together, pushed to the back of the mouth, and squeezed into the throat by the tongue muscles. In the pharyngeal phase, the sensation of food entering the throat sets in motion a wave of muscle contractions that propels the food to the opening of the esophagus (food pipe) where a circular muscle, or sphincter, opens to allow passage through the esophagus into the stomach. Food travels through the esophagus in much the same way as it does through the throat – by a series of muscle contractions activated by sensory input.

Degenerative neurologic disease can create problems in the swallowing system similar to those affecting other sensory/motor functions elsewhere in the body: decreased sensory input, muscle weakness or visible atrophy, and incoordination of movement. Symptoms may occur such as difficulty in chewing or moving food around with the tongue, inability to swallow (initiate the "swallowing reflex"), the sensation of food "getting stuck" in the throat or esophagus, choking on liquids, or regurgitation of food into the mouth or nose. Poor vocal cord closure, decreased laryngeal (voice box) elevation, and insufficient or incoordinated breathing patterns can also interfere with swallowing.

Evaluation
A series of tests, involving a number of different medical specialists, can be used to assess swallowing. Because swallowing is a dynamic process, a particularly useful method of evaluation is a videofluoroscopic study – also called a "cookie swallow" or modified barium swallow. A videotaped recording, under radiation, is made while the patient swallows different food consistencies (liquids, pastes, or solids) of radio-opaque material – usually barium. In most facilities this test is performed as a cooperative procedure between a radiologist and a speech pathologist or occupational therapist.

A number of additional medical tests may be recommended based on the results of an initial videofluoroscopic swallowing study.Referral to an ENT (ear, nose and throat doctor) for an indirect laryngoscopy is warranted when there is concern about the ability of the larynx too protect the airway during swallowing. The physician will look in the throat with a special instrument to assess the ability to close the vocal cords, elevate the voice box, and clear the airway of any foreign substance by producing a strong cough.

Fiberoptic bronchoscopy is of similar diagnostic value in looking at the larynx with the increased capabilities provided by the use of sophisticated photographic techniques. The upper airway is also visualized for the presence of infection, bleeding, and tumors or other obstructions that may be causing breathing difficulties or otherwise interfering with swallowing.

Further assessment of the esophagus can be accomplished by endoscopy (insertion, through the mouth, of an instrument capable of allowing the physician to view the food pipe from the inside) or manometry. Esophageal manometry is useful in diagnosing weak or poorly coordinated muscle contraction and dysfunction of the muscle that permits food to pass from the esophagus into the stomach.

CMT individuals can and do have swallowing difficulties; but not all of us show the same degree or combination of symptoms. It is, therefore, important to obtain a thorough evaluation of swallowing and its related systems by medical professionals. And the good news is that many of these problems can be easily compensated for or remediated by therapeutic techniques.

Getting help
Most major medical facilities evaluate swallowing function by videofluoroscopy and selective additional testing. Contacting the Departments of Speech Pathology (Communication Disorders) or Occupational Therapy in area hospitals or rehabilitation centers may be a good place to start for advice. Universities offering training programs for rehabilitation professionals can also be of help.

In the United States, several regional swallowing centers are available for direction and consultation services. The Consumer Division of the American Speech Language and Hearing Association will be able to provide information concerning services available in your area.