Effectiveness of transcutaneous electric nervous stimulation associated with vocal exercises in the treatment of hyper functional voice disorders: controlled, randomized and blind clinical trial

Abstract

Voice disorders associated with vocal hyperfunction (HV) are among the most common conditions in the vocal clinic, with a prevalence of around 65% among voice disorders. Although they are recurrent conditions in the vocal clinic, there is no consensus on the best measures to evaluate and monitor the effect of the treatment of this condition, which compromises the diagnostic and discharge criteria, as well as the interpretation of the effect of therapy offered to these patients. Voice therapy programs, including performing direct and indirect exercises to production, have been recommended for rehabilitation of HV pictures. However, in recent years there has been a growth in the use of Transcutaneous Electrical Stimulation (TNES) in the vocal clinic in the treatment of HV, although this use is not supported by available scientific evidence. On the other hand, low frequency TNES has been used in vocal rehabilitation of women with vocal nodules, demonstrating positive effects on vocal quality and reduction of muscle pain, although there is a scarcity of scientific proof of their effects added to vocal therapy. Thus, considering the prevalence of voice disorders associated with HV and the need to validate new strategies for rehabilitation of these patients, the aim of this research is to verify the effectiveness of low frequency TNES applied simultaneously to the performance of vocal exercises in the treatment of dysphonic individuals with HV. Thus, this research is a controlled, randomized and blind clinical trial. Participants will be randomized into three groups: G1: dysphonic women with HV who will receive application of 12 sessions with low frequency TNES (frequency at 10Hz, 100us phase, motor threshold), with electrode slaying on the thyroid cartilage blade bilaterally) simultaneously performing vocal exercises for 20 minutes; G2: dysphonic women with HV who will receive application of 12 sessions of placebo TNES (same conditions as G1, but without turning on the electrical current apparatus) simultaneously performing vocal exercises; and G3: dysphonic women with HV who will receive application of 12 sessions only with low frequency TNES (same conditions as G1). All will be evaluated for vocal quality (auditory and acoustic perceptual analysis), vocal hyperfunctioning (auditory-auditory, acoustic, aerodynamic, laryngeal and self-assessment of vocal exertion),dinâ vocal mica and laríngeo behavior(d-padrand glottic closure, amplitude and symmetry of vibration of the mucosal wave). Evaluations will be performed before the start of treatment immediately and after one month of vocal treatment. The data will be analyzed using Statistica 15.0 and SPSS 16.0 software, considering a 95% confidence interval. Based on the results found in this research it is expected to provide a scientific evidence base for recommendation or not of a therapeutic proposal with the combined use of low frequency TNES with the vocal exercise program, advancing in the state of the art and developing therapeutic resources for the treatment of this condition with a high prevalence in the vocal clinic. In addition, the collaborative character between UFPB and FOB/USP allows the scientific and technological advances of the two institutions, since the groups of researchers involved have different expertise related to the development of clinical trials, the use of technologies for vocal rehabilitation and the use of technologies to collect data to measure the outcome investigated. Thus, the expectation is to develop new competencies and skills in the groups involved and broaden the evidence base regarding the vocal rehabilitation procedures used in this study. (AU)