Voiced High-Frequency Oscillation or Lax Vox Technique? Immediate Effects in Dysphonic Individuals.

OBJECTIVES: To analyze the immediate effects of voiced high-frequency oscillation (VHFO) and Lax Vox technique on vocal quality and self-reported intensity of vocal and laryngeal symptoms in individuals with behavioral dysphonia. METHODS: This experimental, prospective, randomized cross-over study, investigated thirty adults (15 women and 15 men) with behavioral dysphonia (vocal complaints, altered voice on auditory-perceptual evaluation, vocal nodules or mucosal thickening, and incomplete glottic closure). The outcome variables analyzed were auditory-perceptual analysis, acoustic analysis (voice quality characteristics), and self-reported intensities of vocal and laryngeal symptoms. Each participant performed two exercises-VHFO and Lax Vox technique-in a random sequence for 3 minutes. A 7-day washout period was provided between the exercises. The data were analyzed using the paired t-test and Wilcoxon test (P < 0.05). RESULTS: After VHFO, no significant difference was observed on auditory-perceptual evaluation in all participants, whereas the Lax Vox technique worsened breathiness among women (P = 0.027). VHFO significantly increased the fundamental frequency (P = 0.014) and decreased the noise harmonic ratios for women (P = 0.026). Among men, there was a decrease in shimmer parameter (P = 0.035). Moreover, symptoms such as "lump in the throat" (P = 0.005), "voice loss" (P = 0.017), and "high-pitched voice" (P = 0.023) decreased in women after VHFO, whereas in men, "itchiness" and "hoarseness" (P < 0.001) decreased after VHFO. The Lax Vox technique decreased "hoarseness" (P = 0.003) in women, without any effect in men. CONCLUSION: The VHFO exercise provided more positive immediate effects results than the Lax Vox technique regarding vocal quality and self-reported symptom intensity in participants with behavioral dysphonia.

Voiced High-frequency Oscillation and LaxVox: Analysis of Their Immediate Effects in Subjects With Healthy Voice.

OBJECTIVES: The aim of this study was to analyze the immediate effects of voiced high-frequency oscillation (VHFO) and LaxVox exercises in vocally healthy subjects. METHODS: Thirty adult subjects (15 women, 15 men) with no history of dysphonia or vocal complaints participated in the study. The subjects performed VHFO and LaxVox techniques for 3 minutes in a random order, with a washout period of 7 days. They answered a questionnaire for vocal/laryngeal intensity symptoms, and had maximum phonation time (MPT) /a/, /s/, /z/, and number counting measured. The vowel /a/ was also recorded before and after both techniques for acoustic analysis. After both techniques, the subjects answered a questionnaire about vocal, laryngeal, respiratory, and articulatory sensations. Data were analyzed using the Wilcoxon, and paired t and chi-square tests were used (P < 0.05), as required. RESULTS: There was an increase in high loudness symptom after LaxVox in women, whereas there was a decrease in painful throat, irritated throat, and low loudness symptoms after VHFO in men. After LaxVox, the MPT of /z/ increased in women and after VHFO, the MPT of /s/, /z/, and number counting increased in men. The fundamental frequency variability increased in women after VHFO. The sensations remained unchanged in both groups following the two exercises in women and men. CONCLUSIONS: VHFO and LaxVox techniques had similar effects on vocal and laryngeal symptoms, as a matter of fact, in terms of phonatory and acoustic measures. With regard to vocal symptoms, VHFO showed better immediate effects in men than in women. As a result, the hypothesis H0 is partially refuted.