The optic nerve (ON) is a recently recognized tractional load on the eye during larger horizontal eye rotations. In order to understand the mechanical behavior of the eye during adduction, it is necessary to characterize material properties of the sclera, ON, and in particular its sheath. We performed tensile loading of specimens taken from fresh postmortem human eyes to characterize the range of variation in their biomechanical properties and determine the effect of preconditioning. We fitted reduced polynomial hyperelastic models to represent the nonlinear tensile behavior of the anterior, equatorial, posterior, and peripapillary sclera, as well as the ON and its sheath. For comparison, we analyzed tangent moduli in low and high strain regions to represent stiffness. Scleral stiffness generally decreased from anterior to posterior ocular regions. The ON had the lowest tangent modulus, but was surrounded by a much stiffer sheath. The low-strain hyperelastic behaviors of adjacent anatomical regions of the ON, ON sheath, and posterior sclera were similar as appropriate to avoid discontinuities at their boundaries. Regional stiffnesses within individual eyes were moderately correlated, implying that mechanical properties in one region of an eye do not reliably reflect properties of another region of that eye, and that potentially pathological combinations could occur in an eye if regional properties are discrepant. Preconditioning modestly stiffened ocular tissues, except peripapillary sclera that softened. The nonlinear mechanical behavior of posterior ocular tissues permits their stresses to match closely at low strains, although progressively increasing strain causes particularly great stress in the peripapillary region.

视神经 (ON) 是最近公认的在较大的水平眼球旋转过程中对眼睛的牵引负荷。为了了解内收过程中眼睛的机械行为，有必要描述巩膜、ON，尤其是其鞘的材料特性。我们对取自新鲜死后人眼的标本进行拉伸载荷，以表征其生物力学特性的变化范围并确定预处理的效果。我们拟合了简化的多项式超弹性模型来表示前部、赤道部、后部和视盘周围巩膜以及 ON 及其鞘的非线性拉伸行为。为了比较，我们分析了低应变和高应变区域的切线模量来表示刚度。巩膜僵硬通常从前眼区到后眼区降低。ON 的切线模量最低，但被更硬的护套包围。ON、ON 鞘和后巩膜的相邻解剖区域的低应变超弹性行为是相似的，以避免在它们的边界处出现不连续性。单个眼睛内的区域刚度是适度相关的，这意味着眼睛一个区域的机械特性不能可靠地反映该眼睛另一个区域的特性，并且如果区域特性不一致，则可能会在眼睛中发生潜在的病理组合。预处理适度僵硬的眼部组织，除了软化的周围巩膜。后眼部组织的非线性机械行为允许它们的应力在低应变下紧密匹配，