Spatio-temporal quantification of vocal fold vibrations using high-speed videoendoscopy and a biomechanical model.
Pathologic changes within the organic constitution of vocal folds or a functional impairment of the larynx may result in disturbed or even irregular vocal fold vibrations. The consequences are perturbations of the acoustic speech signal which are perceived as a hoarse voice. By means of appropriate image processing techniques, the vocal fold dynamics are extracted from digital high-speed videos. This study addresses the approach to obtain a parametric description of the spatio-temporal characteristics of the vocal fold oscillations for the aim of classification. For this purpose a biomechanical vocal fold model is introduced. An automatic optimization procedure is developed for fitting the model dynamics to the observed vocal fold oscillations. Thus, the resulting parameter values represent a specific vibration pattern and serve as an objective quantification measure. Performance and reliability of the optimization procedure are validated with synthetically generated data sets. The high-speed videos of two normal voice subjects and six patients suffering from different voice disorders are processed. The resulting model parameters represent a rough approximation of physiological parameters along the entire vocal folds.
Department of Communication Sciences and Disorders, University of South Carolina, Columbia, South Carolina 29208, USA. raphael.r.schwarz@googlemail.com
Raphael
R
Schwarz
Michael
M
Döllinger
Tobias
T
Wurzbacher
Ulrich
U
Eysholdt
Jörg
J
Lohscheller
D000465:Algorithms; D001696:Biomechanical Phenomena; D004724:Endoscopy; D005931:Glottis / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D009991:Oscillometry; D010781:Photography; D014732:Vibration; D014741:Video Recording; D014827:Vocal Cords / Q000033:anatomy & histology / Q000502:physiology*; D014831:Voice