Effects of basilar-membrane lesions on dynamic responses of the middle ear.

BACKGROUND: Numerical simulations can reflect the changes in physiological properties caused by various factors in the cochlea.

AIMS/OBJECTIVE: To analyze the influence of lesions of the basilar membrane (BM) on the dynamic response of the middle ear.

METHOD: Based on healthy human ear CT scan images, use PATRAN software to build a three-dimensional finite element model of the human ear, then apply NASTRAN software to conduct analysis of solid-fluid coupled frequency response. The influence of lesions in the BM on the dynamic response of the middle ear is simulated through the method of numerical simulation.

RESULT: Through comparing experimental data and the frequency-response curve of displacement of BM and stapes, the validity of the model in this paper was verified.

CONCLUSION: Regarding sclerosis in BM, the most obvious decline of displacement and velocity exists in the range of 800-10,000Hz and 800-2000Hz frequency, respectively. The higher degree of sclerosis, the more obvious decline becomes. The maximal decline of hearing can reach from 6.2 dB to 9.1 dB. Regarding added mass in BM, the most obvious decline of displacement exists in the range of 600-1000Hz frequency, and the maximal decline of hearing can reach 4.0 dB. There is no obvious decline in velocity.