The spasmodic dystonia's treatment with botulinum toxin. [Il trattamento della disfonia spasmodica con tossina botulinica].

Blitzer studies first in 1986 the use of botulinum toxin injected into the vocal muscle in order to effort patients voice suffering from Spasmodic Dysphonia (SD). We refer our experience about this kind of treatment made in six female patients affected by SD. Botulinum toxin has been used in many other dystonias such as blepharospasm, torticollis, etc. Its efficacy consists in blocking presynaptic motor endplate, so realizing a chemical muscle paresis. Injection of the toxin into the vocal muscle induces significant improvements in spasmodic dysphonia. We made the injection without anesthesia, unilaterally, transcutaneously, with the electromyograph guida which permits to reach easily the vocal muscle. Authors refer the long term results, the need of repetition of the treatment after 4/7 months and the objective and subjective improvements of treated patients