Optimizing mitomycin C in photorefractive keratectomy: A paired-eye comparison of 15- versus 30-second applications

Purpose To compare the efficacy of 15-s versus 30-s intraoperative applications of 0.02% mitomycin C (MMC) in preventing corneal haze after photorefractive keratectomy (PRK) for moderate myopia. Methods This prospective, paired-eye study enrolled 50 patients (100 eyes) with bilateral moderate myopia (−3.00 to −6.00 D). Each patient underwent bilateral wavefront-optimized PRK. One eye was randomized to receive 0.02% MMC for 15 s, and the fellow eye received it for 30 s. The primary outcome was the incidence and severity of corneal haze, graded on a 0–4 scale at 1 week and 1, 3, and 6 months postoperatively. The secondary outcome was uncorrected distance visual acuity (UDVA). Results The median age was 25.5 years (range, 18–53). Preoperative refractive errors were symmetrical between paired eyes ( P > 0.05). Postoperative corneal haze was minimal and transient. Median haze scores were 0 at all timepoints beyond the 1-week visit. Haze severity decreased significantly over time in both groups ( P < 0.01), with no statistically significant differences between the 15-s and 30-s groups at any follow-up visit (P ≥ 0.08). At 6 months, the median UDVA was 0.00 logMAR in both groups ( P = 1.0). Conclusions A 15-s intraoperative application of 0.02% MMC resulted in comparable rates of corneal haze prevention and excellent visual outcomes to a 30-s application in preventing corneal haze and achieving excellent visual outcomes after wavefront-optimized PRK for moderate myopia. Shorter exposure times may enhance safety by minimizing potential cytotoxic risks.