Impact Of Mitomycin C On Visual Outcomes And Epithelial Remodeling After Photorefractive Keratectomy

To compare visual, refractive, and epithelial remodeling outcomes in patients undergoing photorefractive keratectomy (PRK) with and without intraoperative mitomycin C (MMC).

Refractive Surgery Unit, Department of Ophthalmology, tertiary referral center, Portugal.

Comparative observational study including eyes undergoing PRK for the correction of myopia or myopic astigmatism. Eyes were divided into two groups according to intraoperative use of MMC 0.02%. Outcomes included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive spherical equivalent, and epithelial thickness parameters measured by anterior segment optical coherence tomography preoperatively and at 1 and 6 months postoperatively. Group comparisons were performed using independent sample tests. Normality assumptions were assessed, and appropriate corrections were applied when required.

A total of 55 eyes of 55 patients were included (28 without MMC, 27 with MMC). Preoperative spherical equivalent was higher in the MMC group (−4.66±1.31 D vs −4.01±0.51 D, mean±SD, p=0.019). Both groups showed significant postoperative improvement in UCDVA, with no significant differences at 1 month (0.07±0.20 vs 0.05±0.13 logMAR, p=0.66) or 6 months (−0.01±0.05 vs −0.01±0.07 logMAR, p=0.88). Epithelium mean thickness, mean thickness standard deviation, coefficient of epithelial variation and thickest and thinnest points thickness did not reveal any differences between groups at baseline, 1 month, or 6 months. No cases of clinical haze were reported in this study in both groups at 1 or 6 months. No severe complications were observed.

PRK performed with and without mitomycin C resulted in comparable visual and refractive outcomes, despite higher preoperative spherical equivalent in the MMC group. Detailed epithelial thickness analysis demonstrated that MMC use did not induce significant alterations in global epithelial thickness, variability, or epithelial homogeneity over time. The absence of clinical haze in both groups supports the safety of modern PRK protocols, while the preservation of physiological epithelial remodeling patterns suggests that MMC does not adversely interfere with epithelial behavior. These findings reinforce the role of MMC as a safe adjunct in PRK, providing haze prevention without compromising epithelial remodeling or visual outcomes.