Efficacy of Voice Therapy for Remaining Hoarseness Due to Tension Imbalance Following Medialization Procedures

Medialization procedures, such as type I thyroplasty, arytenoid adduction, and vocal fold injection, are currently popular treatments for hoarseness due to unilateral vocal fold paralysis. However, hoarseness occasionally remains after medialization procedures due to tension imbalance. This tension imbalance causes diplophonia, asymmetry and aperiodic vibrational flutter in travelling wave motion. This is mostly due to incomplete glottic closure, imbalance in muscular tension, and increased air flow through an incompetent glottis. There is no established treatment for tension imbalance. We herein report two cases with remaining hoarseness post-medialization for chronic unilateral vocal fold paralysis. These patients underwent voice therapy using flow phonation to establish respiratory support and a resonant voice to facilitate vocal fold vibration. As a result, the functional vocal fold vibration, aerodynamic assessments, acoustic analysis findings and self-rated condition improved in both cases after therapy. These results suggest that voice therapy involving flow phonation and resonant voice may help improve the vocal function in cases of tension imbalance with dysphonia. Further studies with a larger number of participants or a prospective randomized controlled trial are warranted.