人工听骨不同接入方式对耳结构动力响应的影响

Effect of different connecting methods for artificial ossicle on dynamic response of ear

目的研究人工听骨接入方式对听力恢复的影响。方法通过CT扫描技术,结合自编C++程序读取CT数据中体单元建立人耳结构几何模型,将几何模型导入PATRAN中建立有限元数值模型。采用频率响应方法对耳结构模型进行流固耦合计算,同时分析人工听骨不同接入方式及接入位置对耳结构声音传导的影响。结果通过对正常人耳的动力响应分析,得到数值模型中计算出的鼓膜凸与镫骨底板振幅与试验数据吻合,验证本文模型的正确性。结论接在鼓膜凸的位置其动力响应最好,镫骨振幅高于其他连接方式。即人工听骨接在鼓膜凸的位置比较吻合人耳的生理功能,其重建听力效果更好。

Objective To study the effects of the different connecting mode of artificial ossicle on hearing restoration.Method Geometrical model of human ear was established by an original C＋＋ program based on clinical CT data,and imported this geometrical model into finite element software PATRAN to build up the numerical finite element model of human ear structure.Based on the finite element model,the fluid-solid coupling was computed by harmonic response analysis method,and the effect of sound conduction on ear structure was analyzed according to different implantable methods and positions of artificial ossicle.Results The validity of this numerical model is confirmed by comparing the amplitude of umbo and stapes footplate on numerical model which is gained by dynamic response analysis on normal ear structure with published experimental measurements on human temporal bones.Conclusions Connecting artificial ossicle to tympanic membrane at its central position is optimal for the dynamic response of ear structure as the amplitude of stapes footplate under this situation is slightly higher than other connecting methods since it conforms to physiological function of human ear,and the effect of hearing recovery could be better.