The effect of voice therapy on voice fatigue and vocal tract discomfort in patients diagnosed with muscle tension dysphonia

The aim of our study was to evaluate participant diagnosed with muscle tension dysphonia before and after voice therapy by means of acoustic, aerodynamic, auditory-perceptual and self-assessment scales and to examine in detail how the parameters measured have changed after voice therapy. A total of 30 participant, 17 males and 13 females, aged between 21 and 68, were included in the study. Participants were implemented holistic voice therapy program in an 8 sessions, one face-to-face session per week. The voices of all participants were analyzed before and after the therapy by acoustic analysis (F0, jitter, shimmer, NHR), aerodynamic measurement (MPT and s/z ratio), auditory perceptual assessment (GRBAS) and patient self-assessment scales (VHI, VFS, VTDI). The post-therapy evaluation of the participants was completed 1 week after the last therapy session.Findings obtained from the study have revealed that shimmer, jitter, NHR, SPI and MFS were statistically significantly different in terms of acoustic and aerodynamic parametersbefore and after the therapy (p<0.05). GRBAS, VHI-10, VFS, and VTDI scores of the participants after the therapy were significantly lower than beginning (p<0.05).In conclusion, it was observed that the holistic voice therapy was effective in improving subjective and objective measurements of participants diagnosed with muscle tension dysphonia and, accordingly the voice quality of the patients remedied significantly. Finally, it is necessary to examine the long-term results of voice therapy in order to evaluate the permanence of improvements in participants' voice quality.