Morphologic changes in laryngeal vibration associated with increasing air flow

Abstract

Data from the in vivo canine model have indicated that laryngeal resistance is not constant during constant levels of vocal fold stiffness, but varies inversely as a function of air flow. This study was undertaken to determine what morphologic changes in the glottis account for the resistance measurements. Three animals were examined stroboscopically during increasing air flow with constant vocal fold stiffness. Glottal dynamics were measured including photoglottography, electroglottography, and subglottic pressure. Analysis of computerized stroboscopic images indicated that increasing air flow had no effect on the glottal chink (vocal press contact). Increasing air flow was associated with an increase in the amplitude of peak opening and an increase in the glottal area integral.