Vocal Tract Adjustments of Dysphonic and Non-Dysphonic Women Pre- and Post-Flexible Resonance Tube in Water Exercise: A Quantitative MRI Study

Objective To compare vocal tract (VT) adjustments of dysphonic and non-dysphonic women before and after flexible resonance tube in water exercise (FRTWE) at rest and during phonation using magnetic resonance imaging. Study Design Prospective study. Methods Twenty women, aged 20–40 years, 10 dysphonic with vocal nodules (VNG) and 10 controls (CG), underwent four sets of sagittal VT MRI: two pre-FRTWE, at rest and during phonation, and two post-FRTWE, during phonation and at rest. The subjects performed 3 minutes of exercise. Nine parameters at rest and 21 during phonation were performed. Results Pre-FRTWE, eight significant differences were found, three at rest and five during phonation: at rest - laryngeal vestibule area, distance from epiglottis to pharyngeal posterior wall (PPW) and interarytenoid complex length were smaller in the VNG; during phonation - laryngeal vestibule area, angle between PPW and vocal fold (VF), epiglottis to PPW, and anterior commissure of the larynx to laryngeal posterior wall were smaller in the VNG; tongue area was larger in the VNG. Post-FRTWE, only three significant differences were found, two during phonation and one at rest: during phonation - angle between PPW and VF and the membranous portion of the VF length were smaller in the VNG; at rest - distance from epiglottis to PPW was smaller in the VNG. Conclusions Results suggest that the habitual VT adjustments of dysphonic and non-dysphonic women are different at rest and during phonation. The FRTWE promoted positive VT changes in the VNG, reducing the intergroup differences.