Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: TUESDAY, March 17, 1992 TAG: 9203170139
SECTION: EXTRA PAGE: EXTRA 3 EDITION: METRO
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DATELINE: LENGTH: Long
Both had developed a perplexing disorder, now called spasmodic dysphonia, that affects the muscles controlling the vocal cords. It changes normal speech into strained, strangled or whispered sounds marked by sudden starts and stops. It can make normally sociable people reluctant to go out in public or talk on the telephone.
The problem, while not as common as stuttering, has attracted considerable professional attention in recent years, partly as a result of innovations in diagnostic tools and the discovery of a treatment that relieves muscle spasms and gives most patients at least a temporary reprieve.
Some medical centers now specialize in it and other speech disorders. The largest is at Columbia Presbyterian Medical Center in New York. There also is a national organization, the National Spasmodic Dysphonia Association, a newsletter, Our Voice, and groups to help patients cope.
Dysphonia refers to pathological changes that affect the vocal cords and result in abnormal sound production. The normal voice may become rough, breathy, tight, halting or too high or too low.
Various abnormalities can cause such changes, including cancer of the larynx, neurologic disorders that paralyze the vocal cords and polyps or inflammation affecting the workings of the tissue around the vocal cords.
In spasmodic dysphonia (formerly called spastic dysphonia), the problem is now widely believed to originate with the nerve cells in the base of the brain that control the muscles in the larynx, or voice box.
These muscles operate the vocal cords, allow them to stretch or shrink, come together or separate to JANE BRODY produce various sounds. Instead of contracting and relaxing normally, the muscles go into spasms that impede the flow of air through the vocal cords.
Whereas stutterers have trouble producing specific sections of words, people with spasmodic dysphonia have trouble getting each word out, according to Dr. Keith Clark, an ear, nose and throat specialist at the University of Oklahoma Health Sciences Center in Oklahoma City.
"There's something wrong with the way the brain is working to control the muscles," he said. A two-year study of 45 patients with spasmodic dysphonia at the Dallas Center for Vocal Motor Control found neurological abnormalities that could account for speech difficulties in 76 percent of them.
Although the cause or causes are not yet understood, experts say the problem is not vocal abuse or strain. Rather, it is one of several disorders grouped under the term dystonia, syndromes characterized by sustained muscle contractions.
Other forms include blepharo-spasm, involuntary closing of the eye and excessive blinking; torticollis, abnormal movements and postures of the head and neck; and writer's cramp, associated with an extremely tight grip and abnormal posture of the hand, arm and shoulder when writing.
Spasmodic dysphonia typically starts between the ages of 40 and 50, and affects more women then men. In about one-fifth of cases, there is a family connection attributed to an abnormal gene on chromosome 9. The onset is usually gradual.
In most people, no specific cause can be determined, although some cases seem to be touched off by a physical trauma such as the insertion of a breathing tube, medications like Haldol and Phenergan, viral infections, mini-strokes or exposure to toxic substances like carbon monoxide .
Symptoms typically disappear when the person sings and get worse when the person is under emotional stress or has to talk on the phone or to a stranger, contributing to the mistaken impression that the problem is an emotional one. Counseling can help people adjust to their disability, but no amount of psychotherapy can cure this condition, experts say.
It is important first to rule out other disorders that may cause similar symptoms, such as Wilson's disease (a hereditary disorder of copper metabolism), stroke or cancer.
Examinations by three kinds of specialists are useful: a speech pathologist, who evaluates voice production and vocal quality; an otolaryngologist, who examines the vocal cords and their functioning; and a neurologist, who looks for other signs of dystonia or associated neurological disorders.
A doctor can observe the anatomy and functioning of the vocal cords by inserting a flexible laryngoscope through the mouth and making a video recording of the results.
Only a few years ago, the only effective treatment was surgery to cut one of the two main nerves connected to the vocal cords, leaving one vocal cord paralyzed. The benefit was usually temporary, lasting only about five years.
But in recent years doctors have had great success with injections of tiny amounts of botulinum toxin into the muscles that work the vocal cords. This toxin, a deadly poison in much larger doses, relieves the spasm by controlling how muscle fibers fire in response to nerve impulses.
Well-designed clinical studies have shown that the injections, which usually are done through the neck under local anesthesia, can restore normal or near-normal speech in about 80 percent of patients for three to four months. Then another injection is needed.
Botulinum toxin, approved for use in treating blepharospasm and certain facial spasms, has not yet been officially approved by the Food and Drug Administration for treating spasmodic dysphonia, but use for that disorder is not illegal, has been found safe and effective by national medical and governmental organizations and already has become widespread.
Dr. Mitchell F. Brin, a neurologist at Columbia Presbyterian, is looking for patients not previously treated with the toxin to take part in research to determine the best dose and method of administration, as well as ways to prolong effectiveness. The New York Times
by CNB