Bulk changes in posterior scleral collagen microstructure in human high myopia.

Purpose: We aimed to characterize any bulk changes in posterior scleral collagen fibril bundle architecture in human eyes with high myopia.

Methods: Wide-angle X-ray scattering (WAXS) was employed to map collagen orientation at 0.5 mm × 0.

Quantification of collagen fiber structure using second harmonic generation imaging and two-dimensional discrete Fourier transform analysis: Application to the human optic nerve head.

Second harmonic generation (SHG) microscopy is widely used to image collagen fiber microarchitecture due to its high spatial resolution, optical sectioning capabilities and relatively nondestructive sample preparation. Quantification of SHG images requires sensitive methods to capture fiber alignment. This article presents a two-dimensional discrete Fourier transform (DFT)-based method for collagen fiber structure analysis from SHG images.

Glaucoma-related Changes in the Mechanical Properties and Collagen Micro-architecture of the Human Sclera.

Objective: The biomechanical behavior of the sclera determines the level of mechanical insult from intraocular pressure to the axons and tissues of the optic nerve head, as is of interest in glaucoma. In this study, we measure the collagen fiber structure and the strain response, and estimate the material properties of glaucomatous and normal human donor scleras.

Methods: Twenty-two posterior scleras from normal and diagnosed glaucoma donors were obtained from an eyebank.

Effects of age and diabetes on scleral stiffness.

The effects of diabetes on the collagen structure and material properties of the sclera are unknown but may be important to elucidate whether diabetes is a risk factor for major ocular diseases such as glaucoma. This study provides a quantitative assessment of the changes in scleral stiffness and collagen fiber alignment associated with diabetes. Posterior scleral shells from five diabetic donors and seven non-diabetic donors were pressurized to 30 mm Hg.

Depth-dependent changes in collagen organization in the human peripapillary sclera.

Purpose: The collagen structure of the human peripapillary sclera plays a significant role in determining optic nerve head (ONH) biomechanics, and is therefore of interest in the study of glaucoma. The aim of the current work was to map the anisotropic collagen structure of the normal human peripapillary sclera as a function of tissue depth.

Methods: Wide-angle x-ray scattering was used to quantify collagen fibril orientation at 0.