Long-term Dose Stability of OnabotulinumtoxinA Injection for Adductor Spasmodic Dysphonia: A 19-Year Single Institution Experience

Paul Paddle, Inna Husain, Christine Moniz, Scott Turner, Ramon Arturo Franco

Research output: Contribution to journalArticleResearchpeer-review

1 Citation (Scopus)

Abstract

Objectives: Adductor spasmodic dysphonia (AdSD) is a focal dystonia predominantly involving the laryngeal adductor muscles. AdSD is reported to be a largely non-progressive neurological disorder, though fluctuations in symptom severity do occur. Repeated laryngeal onabotulinumtoxinA (BTX-A) injections are the primary management for AdSD. A number of studies have demonstrated long-term dose stability as evidence of this long-term disease stability. Methods: A retrospective review was performed on all patients undergoing BTX-A injections for AdSD from April 1994 to September 2013 by a single laryngologist at a tertiary referral laryngology center. Patient demographics, injection doses, use of diazepam and/or lidocaine, and self-reported vocal function were recorded. Multiple linear regression analyses were performed. Results: 83 patients underwent a total of 1,168 injections over 19 years. The mean starting dose was 2.35 MU (0.79 SD). The mean long-term dose was 2.36 MU (0.79 SD). After adjusting for confounders, the change in the relative dose of BTX-A, with every year elapsed since initial dose was 0.13% (95% confidence interval −0.31 to 0.57%), p = 0.568. Conclusion: BTX-A dose is stable over time in our large cohort of patients treated with bilateral thyroarytenoid injections for AdSD.

Original languageEnglish
Article number70
Number of pages4
JournalFrontiers in Surgery
Volume4
DOIs
Publication statusPublished - 29 Nov 2017

Keywords

  • botox dosing
  • laryngeal botox
  • laryngeal dystonia
  • onabotulinumtoxinA
  • spasmodic dysphonia

Cite this