Ear Biomechanics for Restoration of Hearing

描述(申请人提供)：这个项目的长期目标是确定人类耳朵的结构和机械特性如何影响正常、病理和再造耳朵通过外耳道和中耳到内耳(或耳蜗耳)的声-机械传递。我们的假设是，将我们的人耳三维综合有限元模型应用于临床鼓室测量(一种常用于中耳疾病的诊断工具)和激光多普勒干涉测量(一种潜在的传导性听力损失的临床诊断工具)可以提高渗出性中耳炎(OME)的诊断水平。本文提出了四个具体目标：(1)利用激光干涉测量和鼓室导纳测量，确定中耳结构的改变如何影响从耳道到耳蜗声的传递；(2)测量中耳韧带和鼓膜等中耳组织的力学性质或粘弹性；(3)发展具有中耳结构改变的三维有限元模型对人颞骨的多场(即声学-结构-流体)耦合分析；以及(4)将我们的三维有限元模型结果与鼓室导纳和激光干涉测量的临床测量结果相关联，以提高对OME等中耳疾病的诊断。 该项目采用了四种独特的方法：(A)根据颞骨形态测量的组织图像对整个人类耳朵进行精确的几何重建；(B)利用纳米压痕系统和数字图像相关技术直接、精确地测量中耳组织的粘弹性性质；(C)利用双激光多普勒干涉测量系统改进人类颞骨实验，以同时测量通过中耳的声-机械传导；以及(D)对声音从耳道到中耳和到耳蜗的传播进行声学-结构-流体耦合分析。 这项提议中描述的实验将展示中耳结构和耳蜗负荷的变化如何影响声音在耳朵中的传播。有限元模型将展示潜在的临床应用，如中耳液、韧带切断或移除、听小骨脱节、固定或坏死对中耳传递功能的影响。因此，这一结果将对提高OME的诊断、评估传导性听力损失的手术治疗以及潜在地改善数百万人的生活质量至关重要。

DESCRIPTION (provided by applicant): The long-term goal of this project is to determine how the structure and mechanical properties of human ear affect acoustic-mechanical transmission through the external ear canal and middle ear to inner ear (or cochlea) in normal, pathological and reconstructed ears. Our hypothesis is that incorporation of our 3-D comprehensive FE model of the human ear into clinical tympanometry, a diagnostic tool commonly used on middle ear diseases, and laser Doppler interferometry, a potential clinical tool for diagnosis of conductive hearing loss, can improve the diagnosis of otitis media with effusion (OME). There are four specific aims proposed here: (1) to identify how alterations in middle ear structures affect sound transmission from the ear canal through the middle ear to the cochlea measured with laser interferometry and tympanometry; (2) to measure mechanical properties or viscoelasticity of middle ear tissues such as the ligaments and tympanic membrane; (3) to develop multi-field (i.e., acoustic-structure-fluid) coupled analysis of the 3-D FE model with structural alterations in middle ear on human temporal bones; and (4) To correlate our 3-D FE model results with clinical measurements obtained by tympanometry and laser interferometry for improvement of the diagnosis of middle ear diseases such as OME. Four unique approaches are incorporated in the project: (a) accurate geometric reconstruction of entire human ear based on histological images of temporal bone morphometry; (b) direct, accurate measurement of viscoelastic properties of middle ear tissues using the nanoindentation system and digital image correlation techniques; (c) improved human temporal bone experiment with dual laser Doppler interferometry system to measure simultaneously the acoustic-mechanical conduction through the middle ear; and (d) coupled acoustic-structure-fluid analysis of sound transmission from the ear canal to middle ear, and to the cochlea. Experiments described in this proposal will show how changes in middle ear structure and cochlear load affect the sound transmission in the ear. The FE model will demonstrate the potential clinical applications on how the middle ear fluid, ligament cut or removal, and ossicular disarticulation, fixation, or necrosis affect the middle ear transfer function. Thus, the results will be essential for improving the diagnosis of OME, assessing surgical treatment for conductive hearing loss, and potentially improve the quality of life for millions of people.