LASIK-induced corneal changes after correction of hyperopia with and without application of Mitomycin-C

BACKGROUND: The study aimed to assess the role of intraoperative mitomycin-C (MMC) application during hyperopic LASIK correction (+ 1.00 D to + 6.00 D) by examining topographic corneal changes and incidence of regression over a one-year follow-up period. METHODS: This comparative randomized control study included 68 hyperopic patients (136 eyes) divided into two groups; Group A included 34 patients (68 eyes) that had LASIK with the application of 0.02% MMC for 10 s on the stromal bed after excimer laser treatment, and group B included 34 patients (68 eyes) that had LASIK without MMC application. Uncorrected distance visual acuity (UDVA), refraction, keratometry and topography were recorded at 1st week and 1st, 3rd, 6th, and 12th months postoperation. Predictability and treatment efficacy were also recorded at the end of the follow-up period. RESULTS: Better predictability was noted in group A than in group B at the 6 month and 12 month follow-up visits, with a mean cycloplegic refraction SE of + 0.5 ± 0.31 D in group A and + 0.67 ± 0.39 D in group B at the 6 month visit, and + 0.63 ± 0.37 D in group A and + 0.89 ± 0.48 D in group B at the 12 month visit. The efficacy of the treatment at the end of the follow up period was better in group A than in group B. Group A showed fewer topographic corneal changes than group B. CONCLUSIONS: Intraoperative MMC application during hyperopic LASIK achieves better predictability and efficacy and induces fewer topographic changes and lower regression rate of hyperopia during the first postoperative year. TRIAL REGISTRATION: the Pan African Clinical Trial Registry PACTR201901543722087, on 29 January 2019.