Bradshaw John J, Brown Marcus A, Jiang Yijie, Gan Rong Z
School of Biomedical Engineering, University of Oklahoma, Norman, OK, 73019, USA.
School of Aerospace and Mechanical Engineering, University of Oklahoma, 865 Asp Avenue, Room 200, Norman, OK, 73019, USA.
Ann Biomed Eng. 2025 Mar;53(3):718-730. doi: 10.1007/s10439-024-03659-x. Epub 2024 Dec 8.
Veterans commonly suffer from blast-induced hearing disabilities. Injury to the sensitive organ of Corti (OC) or hair cells within the cochlea can directly lead to hearing loss, but is very difficult to measure experimentally. Computational finite element (FE) models of the human ear have been used to predict blast wave transmission through the middle ear and cochlea, but these models lack a representation of the OC. This paper reports a recently developed 3D FE model of the OC to simulate the response of hair cells to blast waves and predict possible injury locations.
Components of the OC model consist of the sensory cells, membranes, and supporting cells with endolymphatic fluid surrounding them inside the scala media. Displacement of the basilar membrane induced by a 31-kPa blast overpressure derived from the macroscale model of the human ear was applied as input to the OC model. The fluid-structure interaction coupled analysis in the time domain was conducted in ANSYS.
Major results derived from the FE model include the strains and displacements of the outer hair cells, stereociliary hair bundles (HBs), reticular lamina, and the tectorial membrane (TcM). The highest structural strain was concentrated around the connecting region of the HBs and the TcM, potentially indicating detachment due to blast exposure. Including the interstitial fluid in the OC created a realistic environment and improved the accuracy of the results compared to the previously published OC model without fluid.
The microscale model of OC was developed in order to simulate blast overpressure transmission through the fluid-filled cochlea and hair cells. This FE model represents a significant advancement in the study of blast wave transmission through the inner ear, and is an important step toward a comprehensive multi-scale model of the human ear that can predict blast-induced injury and hearing loss.
退伍军人常患有爆炸所致听力残疾。内耳柯蒂氏器（OC）或耳蜗内毛细胞受损可直接导致听力丧失，但通过实验很难测量。人耳的计算有限元（FE）模型已用于预测冲击波通过中耳和耳蜗的传播，但这些模型缺乏对OC的表示。本文报告了最近开发的OC三维FE模型，以模拟毛细胞对冲击波的反应并预测可能的损伤位置。
OC模型的组成部分包括感觉细胞、膜和支持细胞，在中阶内有内淋巴液围绕着它们。将源自人耳宏观模型的31 kPa爆炸超压引起的基底膜位移作为OC模型的输入。在ANSYS中进行了时域内的流固耦合分析。
FE模型得出的主要结果包括外毛细胞、静纤毛束（HBs）、网状板和盖膜（TcM）的应变和位移。最高结构应变集中在HBs与TcM的连接区域周围，这可能表明由于爆炸暴露导致分离。与之前发表的无流体的OC模型相比，在OC中包含间质液创造了一个更真实的环境并提高了结果的准确性。
开发OC微观模型是为了模拟冲击波超压通过充满液体的耳蜗和毛细胞的传播。这个FE模型代表了冲击波通过内耳传播研究中的一项重大进展，是朝着能够预测爆炸所致损伤和听力丧失的完整多尺度人耳模型迈出的重要一步。
