Voice Therapy Outcome Post Transoral Thyroarytenoid Myoneurectomy in Adductor Spasmodic Dysphonia: A Case Series

Abstract

ObjectivesPost-operative evaluations of patients, who undergo of trans-oral thyroarytenoid myoneurectomy using CO2 laser for the treatment of Adductor Spasmodic Dysphonia (ASD), reveal some residual laryngeal symptoms such as intermittent spasms, vocal effort, and stiffness in laryngeal muscles which can be identified on Videolaryngo-stroboscopy by patterns of muscle tension dysphonia and mucosal wave, and as deviations in acoustic perceptual measures. This study aims to document these vocal symptoms observed post-operatively, and most importantly highlight the need for voice therapy post-operatively and report the short-term vocal outcomes post-therapy. Study designRetrospective Case series MethodThe case series includes 5 patients, 3 females and 2 males, in the age range of 40 to 76 years, who underwent Transoral thyroarytenoid myoneurectomy using CO2 laser for severe ASD. The assessment protocol to document pre-therapy (three-week post-op) and post-therapy (after 1 month of therapy) findings included Videolaryngo-stroboscopy, Maximum Phonation Time (MPT), VHI-10 GRBAS, and MDVP (Acoustic voice analysis). Voice therapy regimen included Resonant Voice Therapy (RVT), Semi-occluded vocal tract exercises (SOVT), Vocal Function Exercises (VFE), and/or breath support exercises customized for individual symptoms. ResultMuscle Tension Dysphonia (MTD) of varying grades, MPT less than 10 seconds, deviant F0, mild to moderate degrees of perceptually rough and predominantly strained voice were noted in the pre-therapy evaluation. Following 1 month of voice therapy, changes noted were a reduction in strained and rough voice quality and an increase in MPT and muscle tension. Improvement of almost all parameters of MDVP tended towards normative as compared to pre-therapy including F0. ConclusionVoice therapy initiated at the earliest recovery stage postoperatively does lead to positive short-term vocal outcomes in patients with severe ASD. It is necessary to have long-term follow-ups and aim for the maintenance of satisfactory vocal outcomes.