A Case Report in Changes in Phonatory Physiology Following Voice Therapy: Application of High-Speed Imaging

Abstract

To clinically evaluate changes in vocal fold vibration and voice production caused by voice therapy in hoarseness resulting from contact granuloma. Single-subject before-after prospective study using multiple measures of vocal function. A 6-week program of vocal function exercises (VFEs) was conducted using multiple assessments of vocal function to identify and measure the changes pre- and posttreatment, in a 51-year-old male with unilateral contact granuloma. Multiple outcome measures were recorded. High-speed digital imaging (HSDI) measures of voice onset time (milliseconds), open quotient, speed quotient, maximum amplitude, peak closing velocity, peak-to-average opening velocity, and peak-to-average closing velocity were derived from motion data. Acoustic measures of maximum phonation duration (seconds), noise-to-harmonic ratio, average fundamental frequency (hertz), the lowest fundamental frequency (hertz), and the highest fundamental frequency (hertz); aerodynamic measures of expiratory volume (milliliter) and mean expiratory airflow (liter/second); stroboscopic measures of glottal closure and phase closure; and perceptual assessment of voice quality (total score) using the Consensus Auditory-Perceptual Evaluation of Voice were obtained. Stroboscopic, acoustic, aerodynamic, and audioperceptual measures were minimally informative related to pre- and posttreatment vocal function in a patient with contact granuloma. HSDI measures provided multiple physiologic and kinematic measures demonstrating pre- and posttreatment efficiency of vocal function, including vibratory motion, closure, and impact stress. The results have implications for the use of high-speed imaging to identify and measure change in phonatory physiology in patients with contact granuloma. Changes in phonatory physiology support the use of voice therapy techniques, such as VFEs that facilitate a semioccluded vocal tract for treatment of contact granuloma.