Author : Dongfang Qian
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (119 download)
Book Synopsis Finite-element Modelling of Middle-ear Vibrations Under Quasi-static Pressurization by : Dongfang Qian
Download or read book Finite-element Modelling of Middle-ear Vibrations Under Quasi-static Pressurization written by Dongfang Qian and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Early identification of hearing loss is important because if untreated it can lead to delayed language development and other difficulties. Current tools for newborn hearing screening are subject to excessively high false-positive rates. Tympanometry is a promising tool for improving screening tests by evaluating the condition of the middle ear, but it is poorly understood in newborns. Tympanometry involves large deformations, non-linear responses, viscoelastic (time-dependent) effects, and complex dynamic responses, which make it hard to model. A previous gerbil finite-element model developed in our lab was the first numerical simulation of tympanometry involving the simultaneous application of large quasi-static pressures and small sound pressures, and it succeeded in replicating some features of tympanometry. However, the model involved over-simplified anatomical details of the ossicles to reduce the computational cost. The goal of this study was to improve the model by adding a representation of the incudostapedial joint and its surrounding structures.The model employed a quasi-linear visco-hyperelastic model with several time constants in a Prony series. Material properties were taken from previous models and publications. The tympanic membrane was assumed to be homogeneous and nearly incompressible. The loads, combining high quasi-static pressures with low-amplitude sound pressures, both low-frequency pure tones and wideband chirps, reflected the conditions in tympanometry. The model was verified against our previous models, and validated against data from the literature and our recent laser vibrometry data for the pressurized gerbil middle ear. The model demonstrated experimentally and clinically observed features, including hysteresis and the asymmetry in the vibration amplitude between positive and negative static pressures.This numerical model will help us gain insight into how the middle ear responds to different stimuli and thus open up new approaches to the interpretation of tympanometric measurements"--