In this study, we used SALS (Small Angle Light Scattering) to scan cryosectioned human ONH (optic nerve head) tissues and quantified the collagen distribution in the LC (lamina cribrosa) and peripapillary sclera using constrained Von mises distribution. Results showed the collagen fibers in the LC were mostly radially aligned, consistent with SHG (Second Harmonic Generation) images. We also observed a strong circumferential fiber ring, located near but a distance away from the scleral canal boundary. 2D finite element models were constructed using nonlinear, anisotropic, heterogeneous hyper-elastic constitutive equations, incorporating the fiber distribution information from the SALS experiments. The simulations and following sensitivity analysis showed that the strong fiber ring in the peripapillary sclera reduced the strain level near the scleral canal, created a low strain ring. This indicated that collagen fiber ring might act as a self-protection mechanism for the eye.
Microstructure is measured using small angle light scattering.