Purpose:
Researchers have suggested that the microstructural organization of the posterior sclera may correlate with the development of glaucoma. Previous studies in our laboratory of normal posterior scleras have shown that the microstructure is significantly different between Caucasians and African Americans, with little differences occurring with age. The purpose here was to investigate if differences in microstructure exist between different posterior locations in glaucomatous eyes from Caucasian donors.
Methods:
Four specimens (temporal, nasal, superior, and inferior), ~ 1cm by 1cm in size, were isolated from each posterior sclera of 14 glaucomatous eyes (7 donors). Each specimen was snap frozen in liquid nitrogen and cryosectioned at 70 µm. Sections were then placed on slides and dehydrated in a graded glycerol solution. A small angle light scattering (SALS) device was used to investigate the matrix organization. The percent occurrences of fiber angles within equatorially (0°-45° & 135°-180°) and meridionally (45°-135°) aligned bins were quantified automatically with an in-house MATLAB post-processing software. The microstructural differences in different locations were investigated across the entire depth, and in three normalized layers (inner, middle and outer). A one-way ANOVA was used to test statistical differences.
Results:
The mean and standard deviation of percent occurrences for equatorial fibers across the entire depth are shown in Figure 1. There was no statistically significant difference between locations across the entire depth (p=0.956) or in each layer (inner p=0.788; middle p=0.488; outer p=0.64). The percent occurrences of equatorial fibers were slightly higher in right eyes, but the difference was not significant. All glaucomatous eyes had a strong preference of equatorial alignment.
Conclusions:
Locational differences in the microstructure of glaucomatous sclera did not occur in the 7 donors investigated in this study.
Keywords: extracellular matrix • sclera • imaging/image analysis: non-clinical