Laryngeal dystonia: Phenomenology, genetics, and management

Abstract

Laryngeal dystonia is a task-specific movement disorder causing abnormal movement of the adductor or abductor muscles of the vocal folds. In 1984, Blitzer pioneered the first use of onabotulinum toxin A to treat this disorder. Over 1400 patients were diagnosed with laryngeal dystonia in the last thirty years. In this paper, we summarize their clinical and endoscopic findings as well as treatment results. We also summarize the underlying genetics of the disorder.82% of patients were diagnosed with adductor type laryngeal dystonia and 17% of patients manifested an abductor laryngeal dystonia. Patients with adductor dystonia were treated with toxin to the thyroarytenoid muscles and those with abductor dystonia were treated with toxin to the posterior cricoarytenoid muscle. All patient achieved greater than 70% improvement in percent normal function. Laryngeal dystonia is a rare movement disorder of the larynx with an incidence of approximately 35.1 per 100,000 individuals (Simonyan et al., 2021). Presently, there is no cure for laryngeal dystonia, but botulinum toxin has shown significant success in treating the symptoms of the disorder.