Quantitative Analysis of Vocal Fold Vibration in Vocal Fold Paralysis With the Use of High-speed Digital Imaging.

INTRODUCTION: The goal of this work was to objectively elucidate the vibratory characteristics of vocal fold paralysis (VFP) using high-speed digital imaging (HSDI).

METHODS: HSDI was performed in 29 vocally healthy subjects (12 women and 17 men) and in 107 patients with VFP (40 women and 67 men). Then, the HSDI data were evaluated by visual-perceptual rating, single-line kymography, multiline kymography, laryngotopography, and glottal area waveform analysis.

RESULTS: Patients with VFP compared with vocally healthy subjects revealed more frequent incomplete glottal closure, greater asymmetry in amplitude, mucosal wave, frequency, and phase, as well as larger open quotient, smaller speed index, larger maximal and minimal glottal area, and smaller glottal area difference. Paralyzed vocal folds in VFP revealed reduced mucosal wave than nonparalyzed vocal folds in VFP or in intact vocal folds in vocally healthy subjects.

CONCLUSIONS: HSDI was effective in documenting the characteristics of vocal fold vibrations in patients with VFP and in exploring the vibratory disturbance for estimating the severity of dysphonia.