People with spasmodic dysphonia have muscle spasms in the vocal folds that interfere with their speech. The preferred treatment for adductor spasmodic dysphonia, a form in which the vocal folds are closed and speech sounds strangled, is injections with Botox. Researchers looked at how well that works.
What the researchers wanted to know: How much does Botox improve the speech of people with adductor spasmodic dysphonia?
What they did: Forty-two adults with adductor spasmodic dysphonia read a sample text out loud, and six listeners scored the sound of their voice. The patients made recordings before and after the Botox injection, and the researchers also had 42 healthy adults, matched to the patients for age and sex, read the texts.
What they found: Before Botox, voices sounded strangled and irregular; after the injection, those attributes got better, but voices were more likely to sound breathy. Even after treatment, the patients still didn't sound as good as the normal controls. Older people didn't improve as much as younger people did.
What the study means to you: Botox makes people with adductor spasmodic dysphonia sound better but not normal. And since older people didn't benefit as much, they might think twice about getting the shots.
Caveats: The symptoms of this disorder vary a lot between different patients; another study might find different results.
Find out more: An explanation of spasmodic dysphonia from the National Institute on Deafness and Other Communication Disorders
Read the article: Cannito, M.P., et al. "Perceptual Analyses of Spasmodic Dysphonia Before and After Treatment." Archives of Otolaryngology-Head & Neck Surgery. Dec. 2004, Vol. 130, pp. 1393-1399.
Abstract online: http://archotol.ama-assn.org