title: Computation of physiological human vocal fold parameters by mathematical optimization of a biomechanical model.
abstract: With the use of an endoscopic, high-speed camera, vocal fold dynamics may be observed clinically during phonation. However, observation and subjective judgment alone may be insufficient for clinical diagnosis and documentation of improved vocal function, especially when the laryngeal disease lacks any clear morphological presentation. In this study, biomechanical parameters of the vocal folds are computed by adjusting the corresponding parameters of a three-dimensional model until the dynamics of both systems are similar. First, a mathematical optimization method is presented. Next, model parameters (such as pressure, tension and masses) are adjusted to reproduce vocal fold dynamics, and the deduced parameters are physiologically interpreted. Various combinations of global and local optimization techniques are attempted. Evaluation of the optimization procedure is performed using 50 synthetically generated data sets. The results show sufficient reliability, including 0.07 normalized error, 96% correlation, and 91% accuracy. The technique is also demonstrated on data from human hemilarynx experiments, in which a low normalized error (0.16) and high correlation (84%) values were achieved. In the future, this technique may be applied to clinical high-speed images, yielding objective measures with which to document improved vocal function of patients with voice disorders.
authors: Department of Phoniatrics and Pediatric Audiology, University Hospital Erlangen, Medical School, Erlangen, Germany. anxiong.yang@uk-erlangen.de
authors: Anxiong
authors: A
authors: Yang
authors: Michael
authors: M
authors: Stingl
authors: David A
authors: DA
authors: Berry
authors: Jorg
authors: J
authors: Lohscheller
authors: Daniel
authors: D
authors: Voigt
authors: Ulrich
authors: U
authors: Eysholdt
authors: Michael
authors: M
authors: Dollinger
mesh_terms: D000465:Algorithms; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007828:Laryngoscopy; D008297:Male; D008954:Models, Biological; D010699:Phonation; D011312:Pressure; D015203:Reproducibility of Results; D014732:Vibration; D014741:Video Recording; D014827:Vocal Cords / Q000033:anatomy & histology / Q000502:physiology*; D014831:Voice