Spasmodic dysphonia is a movement disorder that afflicts about one in every 5,000 people. It is a form of dystonia, which involves involuntary, repetitive, sustained muscle contractions.
In this condition, patients experience involuntary spasms in the muscles of the larynx, which causes voices to sound strained, quivery and hoarse and words garbled.
The first signs of spasmodic dysphonia typically appear in people aged 30 to 50, but the cause is unknown.
Something, though, causes the brain to miscommunicate with the larynx, triggering the spasms.
There is no cure. But during the past 10 years, doctors specializing in voice disorders have settled on a strange, and somewhat scary, method of treating the symptoms: They inject a mild concentration of the botulism toxin into the larynx. They poke a needle through the neck.
The poison binds itself to nerve endings at the points where the nerves join muscles. The nerves, then, cannot signal the muscles to contract.
As food poisoning, botulism can cause death from suffocation. As a treatment for spasmodic dysphonia, the toxin, in small amounts, weakens the muscles in the larynx, stops the spasms and restores normal speech.
The injections should be repeated every three to six months, or whenever the Botox wears off and the spasms start again.
Doctors use Botox in various ways when they want to relax a muscle.
Some dermatologists, for instance, use Botox to eliminate worry lines, crow's feet, and other wrinkles caused by contractions of facial muscles. Botox has also been used, on a limited basis, to treat spasticity in children with cerebral palsy.
-- Jeffrey Cohan