视乳头的结构和力学特性对筛板变形的影响

目的:建立包含筛板的全眼球轴对称模型，分析视乳头的结构和力学特性对青光眼患者筛板变形的影响。方法:基于青光眼患者和正常对照组的视乳头结构参数数据，并参考文献结果，建立包含筛板的全眼球轴对称有限元模型；分析视乳头的力学特性和结构参数对筛板变形的影响。结果:眼压升高会导致筛板后移，且随着眼压的升高，筛板变形程度增大。巩膜、筛板和硬脑膜的弹性模量对筛板变形的影响程度较大；且筛板厚度、视杯深度、视杯宽度均对筛板变形有影响。青光眼患者的眼底结构参数、力学特性会使其筛板对眼压和颅压的作用更敏感。结论:有限元方法可用于筛板变形影响因素的研究，为青光眼早期诊断提供参考。

Effects of mechanical properties and structure of optic nerve head on the deformation of lamina cribrosa

Abstract: Objective To study the effects of mechanical properties and structure of optic nerve head (ONH) on the deformation of lamina cribrosa based on an axisymmetric model of eyeball including lamina cribrosa. Methods An axisymmetric finite element model of eyeball including lamina cribrosa was established based on the geometrical parameters of the ONH of glaucoma patients and normal controls, and with reference to the results of the literature. The effects of mechanical factors and geometrical parameters of ONH on the deformation of lamina cribrosa were analyzed. Results Increased intraocular pressure made lamina cribrosa move backward, and as intraocular pressure was increased, the degree of lamina cribrosa deformation was increased. The Youngs modulus of sclera, lamina cribrosa and dura mater had great effects on the deformation of lamina cribrosa. Moreover, thickness of lamina cribrosa, cup depth and cup width all affected the deformation of lamina cribrosa. Due to the specific structure and mechanical properties of glaucoma patients, the lamina cribrosa of glaucoma patients was more sensitive to intraocular pressure and intracranial pressure. Conclusion The finite element method can be used to study the factors affecting the deformation of lamina cribrosa, thereby providing some reference for the early diagnosis of glaucoma.