COMPREHENSIVE DESCRIPTION OF CLINICAL FEATURES OF LARYNGEAL DYSTONIA AND DYSTONIC VOCAL TREMOR| ACTA Otorhinolaryngologica Italica

Abstract

Objective. This study aimed to characterize laryngeal dystonia (LD) phenotypes using combined classification criteria and to evaluate treatment outcomes with BoNT-A.

Methods. The study retrospectively reviewed patient medical records from our clinic over ten years to identify cases of LD. We classified LD subtypes (adductor, abductor, mixed) and dystonic vocal tremor (DVT) based on updated criteria.

Results. We analyzed 75 cases, predominantly adductor LD (60%) and DVT (28%). Eighty-four per cent of patients were female, diagnosed around 68 years old. The DVT group had late-onset dysphonia that worsened over time and was associated with essential tremor in almost half of the cases. Subjects with mixed LD had the greatest increase in VHI over time and the longest duration of disease, in all cases associated with DVT. Abductor LD cases had the most severe dysphonia (VHI:73.3). Two-thirds of the cases received BoNT-A therapy, most were AdLD who received treatment the longest and had the lowest rate of treatment refusal.

Conclusions. A correct LD classification aids in diagnosis, prognosis, and therapy planning, it should be dynamic and evolving with the patient's history. However, there is a lack of data in literature on certain LD aspects, emphasizing the need for further research to impact clinical practice.