To investigate the motion of ossicular chain and the input to cochlear partition when static pressure is changed,finite element model was employed to analyze the effects of ear-canal air pressure on dynamic response of middle ear and acoustic input to cochlea. At first,based on the FE analysis and experimental data of middle ear response in the literature,an empirical formula was derived to fit the material parameters of the middle-ear soft tissues as the pressure-dependent elastic modulus relative to the ear-canal static pressure. Then,the influence of static pressure on the mobility of the middle ear and the cochlear input,including the stapes displacement,velocity and the differential pressure between the oval window and round window was evaluated by the pressure-induced stiffening of the middle-ear structure. The satisfactory agreements between the computational result and the corresponding experimental data in the literature indicate the validity of the model for simulating the ear-canal air pressure effects on middle ear transfer function. The results show the influences of positive and negative canal pressure on the movement of the middle ear is different,and under the low frequency range(0 ~600 Hz) ,the change of the differential pressure between oval window and round window is slightly larger than that on the stapes displacement with respect to ear-canal static pressure.%为分析静压变化对中耳听骨链运动和耳蜗输入的影响,运用有限元模型研究外耳道静压导致的中耳声音传递功能和耳蜗激励输入改变.首先,根据相关实验测量数据并结合有限元分析,拟合了耳道静压力与中耳各构件有效弹性模量关系的经验公式；然后,通过材料参数的改变模拟压力造成的中耳结构刚度增加,分析耳道静压对中耳机动性的影响和不同耳道压力下镫骨底板位移、速度和耳蜗两窗压力差的变化.计算结果与相关的文献实验数据有较好的符合,说明所建立的计算模型在模拟静压条件下中耳传递功能方面的合理性.结果表明在低频范围(0～0.6 kHz)外耳道静压对两窗压力差的影响稍大于对镫骨位移的影响.
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