Combined Modality Treatment of Adductor Spasmodic Dysphonia

Introduction The hallmark characteristic of adductor spasmodic dysphonia (ADSD) is irregular and uncontrollable spasms within the intrinsic laryngeal muscles, resulting in erratic disruption of normal voicing. Methods Using a random assignment and the inclusion of a behavioral sham to determine the effect of voice therapy after initial botulinum toxin type A (BTX-A) injections for ADSD, this study examined duration of injection benefit, perceived vocal quality of life from the Voice-Related Quality of Life (V-RQOL) scale, acoustic measures of vocal instability, and perceptual ratings of voice quality. Measures of these variables were collected before initial injection; 3, 7, and 12 weeks postinjection; and immediately before reinjection. Thirty-one individuals with ADSD participated in this study. One-third received no further intervention after BTX-A injection, one-third received a standard 5-week course of voice therapy after BTX-A injection, and one-third received a 5-week course of sham voice therapy after BTX-A injection. Results and Conclusions Significant effects were observed on perceived quality of life and acoustic variables for all participants, over time. Participants who received voice therapy after BTX-A injection did not experience longer injection effect duration or significantly greater improvements in V-RQOL or acoustic variables than participants in BTX-A only or BTX-A plus sham therapy groups. Additionally, perceptual ratings of voice quality improved for all participants in response to BTX-A injection. For participants in this investigation, undertaking voice therapy did not appear to exert significant beneficial effects on the variables of interest.