Spasmodic Dysphonia (SD)

Laryngeal Dystonia

Spasmodic dysphonia (SD) of the larynx is a focal dystonia, thus it is a neurologic disorder. Symptoms of the adductor type (ADSD) are mostly a strained-strangled voice during speech. Singing and whispering are not affected, and other laryngeal functions like swallowing and breathing are also normal.

SD can alternatively be an abductor SD (ABSD) with a breathy voice, or a mixed type. SD can additionally be associated with tremor, which gives the voice a vibrato-like sound. Other muscles of the body may as well be affected by dystonia. Treatment is mainly symptomatic with laryngeal injections of very small amounts of nerve toxin. Injections regularly help for 3 months and have to be repeated.

In ADSD patients, we prefer to inject btx predominantly into the ventricular folds via a transnasal endoscopy approach in the unsedated patient (office based procedure). This painless procedure allows for a very short visit and patients may leave the office within a half an hour after injection.

A patient describes the treatment