title: Classification of unilateral vocal fold paralysis by endoscopic digital high-speed recordings and inversion of a biomechanical model.
abstract: Hoarseness in unilateral vocal fold paralysis is mainly due to irregular vocal fold vibrations caused by asymmetries within the larynx physiology. By means of a digital high-speed camera vocal fold oscillations can be observed in real-time. It is possible to extract the irregular vocal fold oscillations from the high-speed recordings using appropriate image processing techniques. An inversion procedure is developed which adjusts the parameters of a biomechanical model of the vocal folds to reproduce the irregular vocal fold oscillations. Within the inversion procedure a first parameter approximation is achieved through a knowledge-based algorithm. The final parameter optimization is performed using a genetic algorithm. The performance of the inversion procedure is evaluated using 430 synthetically generated data sets. The evaluation results comprise an error estimation of the inversion procedure and show the reliability of the algorithm. The inversion procedure is applied to 15 healthy voice subjects and 15 subjects suffering from unilateral vocal fold paralysis. The optimized parameter sets allow a classification of pathologic and healthy vocal fold oscillations. The classification may serve as a basis for therapy selection and quantification of therapy outcome in case of unilateral vocal fold paralysis.
authors.affiliation: Department of Phoniatrics and Pediatric Audiology, University of Erlangen-Nürnberg, Germany. raphael.schwarz@phoni.imed.uni-erlangen.de
authors.forename: Raphael
authors.initials: R
authors.lastname: Schwarz
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hoppe
authors.forename: Maria
authors.initials: M
authors.lastname: Schuster
authors.forename: Tobias
authors.initials: T
authors.lastname: Wurzbacher
authors.forename: Ulrich
authors.initials: U
authors.lastname: Eysholdt
authors.forename: Jörg
authors.initials: J
authors.lastname: Lohscheller
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D001683:Biological Clocks; D001696:Biomechanical Phenomena / Q000379:methods; D004724:Endoscopy / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008954:Models, Biological; D009068:Movement; D010363:Pattern Recognition, Automated / Q000379:methods; D012815:Signal Processing, Computer-Assisted; D013068:Speech Production Measurement / Q000379:methods*; D014741:Video Recording / Q000379:methods*; D014826:Vocal Cord Paralysis / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology