Epithelial Thickness Profile Change After Corneal Crosslinking: A Retrospective Research

Abstract

Objective: To assess the corneal epithelial remodeling after corneal crosslinking (CXL) and to investigate the relation between topographic parameters and epithelial thickness change. Material and Methods: Sixty-three eyes of 43 keratoconus patients were included in this retrospective study. Keratometry (K) and elevation data were assessed by Scheimpflug topography and corneal and epithelial thickness profile was obtained by anterior segment spectral-domain optical coherence tomography pre-operatively and at the 1st, 6th and 12th months after CXL. Results: Significant decreases were observed in mean K (p=0.014), maximum K (p=0.049), and mean central corneal thickness (p<0.007) after CXL. Superior corneal epithelial thickness was significantly thinner (p<0.001) and the difference between the minimum and maximum epithelial thickness was less at the post-operative first month and didn’t change significantly afterwards. Standard deviation of epithelial thickness across the central 5 mm region statistically decreased in the follow-up period (p=0.008). Conclusion: Significant regularization of the epithelial thickness profile was seen in one year after epithelium-off CXL. Demonstrating the normalization of the corneal epithelium and understanding its impact on the post-operative healing process might contribute to the optimization of treatment protocol.