Protocolo terapêutico baseado em exercícios de trato vocal semiocluído em indivíduos disfônicos: estudo clínico, randomizado e cego

Abstract

Therapeutic protocol based on semi-occluded vocal tract exercises in dysphonic subjects: a blind randomized clinical trial Introducion: The voice therapy can be divided into direct and indirect. The indirect vocal therapy (IVT) are vocal hygiene orientations and voice physiologic production orientations, making the subject aware of harmful vocal habits. The direct therapy can be composed by voice exercises, such as Vocal Function Exercises (VFE) that improve the voice production subsystems: breathing, resonance, and phonation. Another way of direct therapy is using the semi-occluded vocal exercises (SOVTE), these exercises enable better filter and source interaction by the means of acoustic impedance changes. Studies that use a SOVTE protocol are almost zero. Therefore it is believed that a SOVTE protocol can contribute to voice clinic. Objective: Verify the effect of the treatment with SOVTE protocol at self-assessment and voice quality in dysphonic subjects. Compare it with VFE and Vocal Hygiene Approach. Methodology: Randomized and blind clinical trial. Twenty-seven volunteers (12 men and 15 women) were included in this study. They aged between 18 to 50 years old, with vocal complaints about vocal fatigue, and they received the functional dysphonia diagnose. The volunteers were equally divided into three groups: Experimental Group (EG), Vocal Function Exercises Group (VFEG), and Indirect Vocal Therapy Group (IVTG). After they filled the consent form, they were assessed by the researcher at three moments: before the intervention (M1), immediately after it (M2), and one month after it (M3). The researcher used the Vocal Fatigue Index (VFI), selfassessment of the vocal economy, Vocal Handicap Index (VHI), perceptual, and acoustic analysis. For the three groups, the interventions happened twice per week (four weeks) and last 35 minutes. It was used Repeated measures ANOVA test (p<0,05) and Tukey Test. Results: There were statistically significant results in the moment factor for IFV (p<0,001), vocal economy (p=0,007), and VHI (p<0,001). In M2 there was a decrease in the IFV and VHI scores keeping to M3. The vocal economy improved in M2, whereas in M3 it decreases, tending to M1 values. Regarding perceptual analysis, for general degree and roughness in the sustained vowel (p=0,015 e p=0,029) and counting numbers (p=0,036 e p=0,039), they only show that the groups are different. In the acoustic parameter of the fundamental frequency (p<0,001), women show greater values than men and the Cepstral Peak Prominence-smoothed (p=0,019) women show a smaller value than men. Conclusion: The subjects with functional dysphonia e vocal fatigue complaints, the SOVTE protocol is effective as VFE and IVT, regarding vocal fatigue, vocal economy, and vocal impairment. All interventions groups did not have changes at voice quality in this population.