A new order coefficient was introduced to quantize the differences in organization between three different types of treatment applied to porcine corneas: untreated corneas, UVX crosslinked corneas, and corneas treated with riboflavin. Collagen fibers in the stroma were imaged through a depth of 700 mm using forward-scattering second harmonic generation microscopy. Analysis points based on the orientation of the fibers were calculated and the number of points falling within 10° analysis windows was counted. From these points, the order coefficient was calculated as the normalized variance of the number of analysis points in each window. This quantization showed that the UVX crosslinked corneas were more ordered up to a depth of 400 mm in the stroma.
Full reference: James A. Germann, Eduardo Martínez-Enriquez and Susana Marcos. “Quantization of collagen organization in the stroma with a new order coefficient” Biomed. Opt. Express 9, 173-189 (2018).
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