QUANTITATIVE MEASUREMENTS OF THE MEDIAL SURFACE OF THE VOCAL FOLDS IN AN IN VIVO CANINE MODEL
Michael Doellinger, Gerald S. Berke, David A. Berry · 2004
Medial surface dynamics of the vocal folds are important for an understanding of sound generation within the larynx. Such dynamics illustrate the propagation of the mucosal wave which makes voice production possible. Almost universally, in vivo investigations of vocal fold dynamics are performed using endoscopic techniques which allow only a superior view of vocal fold vibration. Hence, the view onto the medial margin is blocked which leads to an observation leak within the vocal fold cycle. In this study, an excised hemi-larynx set-up, is adapted for use with an in vivo canine model. In vivo models allow us to examine effects of intrinsic muscle contraction on the medial surface dynamics of the vocal folds, and provide greater insight into mechanisms of vocal control. Dynamics, of the vocal folds with varying levels of stimulation to the recurrent laryngeal nerve (RLN) will be shown. In particular, quantitative measurements such as fundamental frequency, vocal intensity, and the dynamics of up to 15 different positions along the medial surface of the vocal folds will be presented as a function of RLN innervation. To capture the vibrations, the vocal folds were imaged with a sampling frequency of 2000 Hz, and a spatial resolution of 1024 x 1024 pixels