Can Vocal Therapy With Transcutaneous Electrical Nerve Stimulation (TENS) Followed by Vocal Exercises Reduce Benign Laryngeal Lesions in Dysphonic Women?: Randomized, Blind Clinical Trial

Abstract

To investigate the effectiveness of vocal therapy with the use of low-frequency transcutaneous electrical nerve stimulation (TENS) followed by voice exercises on vocal fold lesion size, vocal quality and quality of life in dysphonic women. 27 women with vocal nodules participated, randomized into to: experimental group (EG)-13 women who received vocal therapy with 12 sessions of 20 min of TENS application (pulse:200μs, frequency:10Hz, motor threshold intensity, electrodes positioned in the trapezius muscle [descending fibers and submandibular region, bilaterally]). Each TENS session was followed by 30 min of vocal exercises; and the Control Group (CG)- 14 women who received 12 sessions with 20 min of application of placebo TENS (same conditions EG, but without receiving the stimulus electric), followed by 30 min of vocal exercise. Before, immediately after and one month after vocal therapy, participants underwent vocal recording for acoustic analysis, vocal self-assessment, laryngological examination and answered voice-related quality of life (V-RQOL) protocol. There was reduction in the size of vocal fold lesions only in the EG, immediately after treatment and one month after treatment. Acoustic analysis showed decreases in SPI values immediately after and one month after treatment in both groups. There was improvement in voice self-perception in both groups after treatment and one month after, but no significant difference in V-RQOL values. TENS followed by vocal exercises produced results similar to vocal therapy without TENS regarding voice quality, self-perception and quality of life in voice. However, vocal therapy with low-frequency TENS followed by vocal exercise was effective in reducing vocal fold lesion size in dysphonic women.