人工中耳作动器激振位置对镫骨运动影响的数值研究  

Numerical analysis of the effect of attachment points of middle ear actuator on stapes movement

作　　者：刘后广[1] 塔娜[1] 饶柱石[1] 

机构地区：[1]上海交通大学机械系统与振动国家重点实验室,上海市200240

出　　处：《中国组织工程研究与临床康复》2010年第52期9819-9822,共4页Journal of Clinical Rehabilitative Tissue Engineering Research

基　　金：国家自然科学基金资助项目(10772121);课题名称:人耳听觉系统与新型智能声桥机理研究;上海交通大学医工交叉研究基金(YG2007MS14);课题名称:压电型植入式智能振子的研究~~

摘　　要：背景:为了解决传统助听器高频增益低、佩戴舒适性差、伴有声反馈等问题,人工中耳成为近20年的一个研究热点。各款人工中耳中作动器的激振部位都有所不同,但这种激振位置的不同对镫骨运动的影响鲜有研究。目的:针对目前创伤较小的人工中耳普遍采用的两种激振位置,分析作动器激振位置对激振效果的影响。方法:在已建立的人体中耳三维有限元模型的基础上,分别在砧骨体和砧骨长突处施加相同幅值的激振力。再分别改变激振力的倾角,模拟手术过程中存在的误差。对以上4组力作用下镫骨底板位移进行分析,并与正常人耳在声激励下的镫骨运动情况进行对比。结果与结论:同样大小的听力损失补偿,作动器激振砧骨长突所需的激振力较小;无论选哪处激振位置,镫骨位移都会随着激振力方向的改变而改变;砧骨体激振力方向与镫骨纵向轴倾斜45°后,镫骨在中高频段的主要运动将不再由活塞式运动构成。结果提示,砧骨长突是人工中耳作动器较理想的激振位置,所需激励力较小,且最终补偿效果对植入手术偏差造成的激励力方向倾斜不太敏感。BACKGROUND：To overcome problems in conventional hearing aids such as low gain at high frequencies,discomfort in occlusion of the external ear canal and acoustic feedback,middle ear implants have been developed over the past two decades. Different types of middle ear implants always have their actuators stimulated different positions of the ossicular chain. The effect of such stimulating placement on stapes movement is rarely investigated. OBJECTIVE：To analyze the effect of the attachment points of their actuator on the movement of the stapes. METHODS：Based on an established human middle ear finite element model,the same amplitude force was applied at incus body and incus long process,respectively. The direction of the excitation force was changed to simulate errors during operation. The stapes displacements stimulated by these forces were calculated and compared with the one normal sound pressure excited. RESULTS AND CONCLUSION：Compensating a same level of hearing loss,small exciting force was required when the attachment point of the actuator was set to the incus long process. The stapes displacement was sensitive to the changes in the direction of excitation regardless of which attachment point was selected. With the actuator attached to the incus body,the stapes piston motion was no longer the main component of the stapes motion in the mid-high frequencies when the excitation＇s direction changes to 45 degree off the longitudinal stapes axis. Results show that the incus long process is an ideal attachment point for actuator as only a small excitation force is required to compensate the same level of hearing loss. In addition,the stapes piston motion is less sensitive to the changes in the direction of the excitation force in this case.

关 键 词：人工中耳 作动器 激励位置 有限元 镫骨 

分 类 号：R318[医药卫生—生物医学工程]