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

OBJECTIVES: Postoperative evaluations of patients, who undergo of transoral 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 (VLS) by patterns of Muscle Tension Dysphonia (MTD) and mucosal wave, and as deviations in acoustic perceptual measures. This study aims to document these vocal symptoms observed postoperatively, and most importantly highlight the need for voice therapy postoperatively and report the short-term vocal outcomes post-therapy.

STUDY DESIGN: Retrospective case series.

METHOD: The case series includes five patients, three females and two males, in the age range of 40 to 76years, who underwent transoral thyroarytenoid myoneurectomy using CO2 laser for severe ASD. The assessment protocol to document pretherapy (3-week postop) and post-therapy (after 1month of therapy) findings included VLS, Maximum Phonation Time (MPT), VHI-10 GRBAS, and Multi-Dimensional Voice Profile (MDVP) (acoustic voice analysis). Voice therapy regimen included Resonant Voice Therapy, semi-occluded vocal tract exercises, Vocal Function Exercises, and/or breath support exercises customized for individual symptoms.

RESULT: 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 pretherapy evaluation. Following 1month 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 pretherapy including F0.

CONCLUSION: Voice 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.