Computational fluid-structure interaction for vocal fold modeling

Abstract

The overall objective of this work is to develop a computational fluid-structure interaction (FSI) model of vocal fold vibration for its future applications in clinical care of voice disorders. One example of such applications is computer model based planning for implant insertion in medialization thyroplasty, i.e., a surgical procedure designed to restore voice for patients with unilateral vocal fold paralysis. We have investigated several fundamental and practical issues involved in the accurate and efficient modeling of the vocal fold dynamics, three-dimensional (3D) flow simulations, and the development as well as validation of patient-specific FSI models. We first studied the significant role of nonlinear strains in the vocal fold vibration using a simple two-dimensional (2D) vocal fold model. Then, we combined an in vivo experimental study using rabbit subjects with 3D FSI modeling to develop an advanced subject-specific model. This model incorporates the anatomical geometry obtained from micro-magnetic resonance imaging of the larynx and also the 3D simulation of both flow and tissue deformation; furthermore, a reduced-order FSI model with simplified flow was developed to identify the unknown elastic properties of the tissue. As a result, the overall model was able to capture the individual-specific characteristics of vocal fold vibration. Finally, application and limitation of the reduced-order FSI model were further studied using a simple vocal fold model.