Patterns of vibratory vocal fold behavior in patients with vocal fold paresis and paralysis studied using HSDI
The use of high-speed imaging was pioneered by Drs. Moore and von Leden in the 1960’s. Using today’s high-speed digital imaging (HSDI) technology, we can evaluate pathological states of vocal fold (VF) vibration in patients with VF paresis and paralysis that could not be resolved by stroboscopy. Twelve patients with VF paresis (n=8) and paralysis (n=4) underwent evaluation with both stroboscopy and with HSDI. In patients with paralysis and paresis, HSDI shows many differences in vibratory abnormalities that could not be observed with stroboscopy. The vibratory differences between the two sides were greatest in paralysis. Distinctly different fundamental frequency (F0) between the two sides were only seen in the paralysis group while paresis showed phase lag and delay in onset of vibration between the sides. Subtle differences in vibration in patients with paresis could be differentiated by objective image analysis and objective waveform analysis of the HSDI using signal analysis of the digital kymogram derived VF vibrogram (VFV).