Evaluation of corneal epithelial remodeling after conventional versus trans-epithelial photorefractive keratectomy for Myopia

Abstract

ABSTRACT Objective To evaluate the changes in epithelial mapping using anterior segment OCT-based tomography (MS-39) after 1 week, 1, 3, and 6 months of manual versus transepithelial photorefractive keratectomy in patients with myopia and myopic astigmatism. Methods We designed, prospective, interventional paired eye study on 52 eyes who underwent photorefractive keratectomy to correct myopia and myopic astigmatism. Each eye of a participant was assigned to a different treatment group; 26 eyes underwent transepithelial Photorefractive keratectomy (transPRK) using Stream Light WaveLight E × 500were categorized as Group A “tPRK group” and 26 eyes underwent conventional PRK by manual epithelium removal and wavefront-optimized PRK using WaveLight E × 500excimer were categorized as Group B “mPRK group.” Epithelial mapping was evaluated for all cases preoperatively and postoperative for six months of follow-up. Results The postoperative central epithelial thickness increased in both groups; it was higher in group B (mPRK) with a statistically significant difference between both groups in the 1-week, 1-month (p < 0.001), and 3-month (p < 0.05) follow-up points with a mean of 57.54 µ,52.40 µ, and 55.23 µ in group A, respectively, and a mean of 65.31µ, 58.50 µ, and 57.41 µin group B, respectively. The postoperative paracentral epithelial thickness increased in both groups; it was higher in group B (mPRK) with a statistically significant difference between both groups at all postoperative follow-up points (p < 0.001) with a mean of 51.20µ, 51.12µ, 53.09µ, and 54.20 µ in group A while with a mean of 65.32µ,64.87µ,58.13µ, and 57.55µ in group B. Conclusion Epithelial thickness mapping after PRK shows epithelial hyperplasia in both mPRK and tPRK methods with a smoother and less fluctuant course in the transepithelial treated eyes, especially in the early preoperative period.