Effect of Electrical Stimulation on the Treatment of Dysphonia: A Systematic Review

Abstract

The aim of this study was to review systematically the literature and to investigate the effects of electrical stimulation in treating dysphonia. This is a systematic review. The publications indexed on the MEDLINE, LILACS, PubMed, Web of Science, and SciELO databases were searched. Original articles with experimental, clinical trial and randomized studies involving a control group and approaching dysphonia treatment with electrical stimulation in humans, regardless of age, gender, or race were included. Those excluded were theses, editorials, comments and opinions, reflexive articles, case studies, experimental studies with animals, models, projects, reports and technical reports, and review articles, as well as articles approaching other alterations, not related to dysphonia. Eleven articles were found and it evaluated the effects of neuromuscular electrical stimulation (NMES) and transcutaneous electrical nerve stimulation on dysphonia caused by vocal fold paralysis, spasmodic dysphonia, behavioral dysphonia, and in patients with vocal fold nodules. The methodological analysis of the articles through the PEDro scale resulted in a mean score of 5.18; the studies were classified as either high quality (N=3) or fair quality (N=8). The results indicated that electrical stimulation had a therapeutic effect on various aspects of dysphonia. However, due to the high risk of bias and the heterogeneity of the studies, it is not possible to state the effectiveness of electrical stimulation in treating dysphonia. Using electrical stimulation as an evidence-based conventional rehabilitation therapy in the treatment of dysphonia cannot yet be done.