Seasonal Effects on Corneal Densitometry and Haze After Mitomycin C-Assisted Photorefractive Keratectomy

Purpose: To investigate whether the season in which photorefractive keratectomy (PRK) with mitomycin C (MMC) is performed influences postoperative corneal transparency considering seasonal variations in ultraviolet (UV) exposure. Methods: This retrospective study included 100 eyes of 50 patients who underwent MMC-assisted PRK for myopic refractive error. Patients were divided into two groups based on the season of surgery: winter (November-April, low UV exposure) and summer (May-October, high UV exposure). All patients were evaluated preoperatively and at 12 months postoperatively. Corneal transparency was objectively assessed using Scheimpflug-based corneal densitometry obtained with the Pentacam system, focusing on the central (0-2 mm) and paracentral (2-6 mm) zones. Postoperative densitometry values were compared between seasonal groups. Results: Corneal densitometry values showed a significant reduction postoperatively compared with preoperative measurements in both central and paracentral zones. When comparing seasonal groups, no statistically significant differences were observed in postoperative densitometry values between eyes operated on during summer and winter months. No clinically detectable corneal haze was observed in any patient throughout the follow-up period. Conclusions: Surgical season did not significantly influence postoperative corneal densitometry or clinically detectable haze formation after MMC-assisted PRK for low-to-moderate myopia, suggesting that deferral during high-UV months may not be necessary with standard postoperative UV protection.