Mitomycin C in photorefractive keratectomy - Effect on epithelialization and predictability

Purpose: To evaluate the effect of topical mitomycin C (MMC) after myopic photorefractive keratectomy (PRK) on epithelialization and predictability Methods: Prospective, randomized, double-masked, same-day, paired eye study. Inclusion criteria: bilateral spherical equivalent (SE) between -6.5 and -10 D, difference of SE between the 2 eyes of <= 0.75 D, central pachymetry > 520 mu m, with a difference between the 2 eyes of < 20 mu m, follow-up 12 months. Planned optical zone was equal in the 2 eyes. After manual deepithelialization and excimer ablation, a Merocel sponge soaked either with MMC 0.2 mg/mL or with balanced salt solution was placed on the stromal bed of either eye for 45 seconds in a randomized fashion. A bandage contact lens was used until epithelialization; fluorometholone 0.1% eyedrops were symmetrically used and tapered in the 2 eyes. Results: Fifty-two patients (23 men; mean age, 33 years) completed the study Preoperative mean SE was -8.07 +/- 0.92 D in the MMC eyes and -7.96 +/- 0.81 D in the control eyes (not statistically significant). Mean epithelialization time was 3.0 +/- 0.69 days in the MMC eyes and 3.0 +/- 0.71 days in the control eyes (not statistically significant). At 12 months, mean SE was 0.47 +/- 0.43 D in the MMC eyes and 0.17 +/- 0.49 D in the control eyes (P < 0.05). Mean haze in the MMC eyes was 0.02 +/- 0.07 and in the control eyes was 0.19 +/- 0. 17 (P < 0.05). Conclusions: MMC did not delay epithelialization and did not induce adverse effects at 12 months. MMC induced a mean 0.47-D overcorrection (5.8% of attempted correction). All eyes treated with MMC had a haze grade <= 0.25.