OBJECTIVES/HYPOTHESIS Although onabotulinum neurotoxin A (BoNTA) has been used for over three decades for the treatment of adductor spasmodic dysphonia, no study has been performed to look at the trend of BoNTA dosages across time. The goal of this study is to evaluate the dosage trends to determine if the dosage necessary for voice improvement in patients increases over time. STUDY DESIGN Ch...

BACKGROUND: Dystonia of the eyelids often spreads to affect other muscles in the craniocervical region. Certain blepharospasm-plus subphenotypes may be clinically unique. METHODS: Seven subjects with the subphenotype of late-onset blepharospasm with apraxia of eyelid opening and cervical dystonia with predominant anterocollis were identified from a database of over 1800 patients with primary d...

Spasmodic dysphonia is a primary focal dystonia characterized by involuntary spasms in the laryngeal muscles during speech production. The pathophysiology of spasmodic dysphonia is thought to involve structural and functional abnormalities in the basal ganglia-thalamo-cortical circuitry; however, neurochemical correlates underpinning these abnormalities as well as their relations to spasmodic d...

Spasmodic dysphonia (SD), or laryngeal dystonia, is an isolated task-specific dystonia of unknown causes and pathophysiology that selectively affects speech production. Using next-generation whole-exome sequencing in SD patients, we computed polygenic risk score from 1804 genetic markers based on a genome-wide association study in another form of similar task-specific focal dystonia, musician's...

Genes causing primary dystonia are rare. Recently, pathogenic mutations in the anoctamin 3 gene (ANO3) have been identified to cause autosomal dominant craniocervical dystonia and have been assigned to the dystonia locus dystonia-24 (DYT24). Here, we expand on the phenotypic spectrum of DYT24 and provide demonstrative videos. Moreover, tremor recordings were performed, and back-averaged electro...

Background Although considerable research has focused on the etiology and symptomology of adductor focal laryngeal dystonia (AD-FLD), little is known about the correlation between clinicians' ratings and patients' perception of this voice disturbance. This study has five objectives: first, to determine if there is a relationship between subjects' symptom-severity and its impact on their quality...