Finite Element Analysis on Frequency Response of Human Eye under Acoustic Excitation / 医用生物力学

ABSTRACT

Objective To study the effects of excitation source, intraocular pressure and material parameters on frequency response of human eye under acoustic excitation. Methods Based on the three-dimensional (3D) finite element model of the whole eye, as well as the deformation and stress distribution of human eye, the effects of various parameters on frequency response of human eye were quantitatively analyzed. Results When other parameters were fixed and only the position and size of the excitation source changed, the amplitude at resonance of human eye (the acoustic excitation source was placed directly above the cornea, at an offset of 45°, and at larger excitation) at 134 Hz was 35, 48 and 133 μm, respectively. When only the intraocular pressure changed, the first-order resonance frequency was almost unaffected by the intraocular pressure, and the resonance frequencies of other orders would shift slightly to the left as the intraocular pressure increased. When only the scleral elastic parameters changed, the resonance frequency of eye tissues increased with the increase of the scleral elasticity. Conclusions The position and size of the excitation source have no effects on resonance frequency of human eye, but they have a greater effect on the resonance amplitude. The material parameters of human eye tissues have a greater effect on the frequency response, and there is a linear relationship between the intraocular pressure and resonance frequency. The results provide the theoretical basis for clinical development of high-performance intraocular pressure monitoring technology.