Effect os mitomycin C on the cicatricial corneal response on laser‐assisted subepithelial keratectomy to correct myopia

Abstract

Abstract Purpose To evaluate the influence of mitomycin C (MMC) on the predictability of refractive results after myopic laser‐assisted subepithelial keratectomy (LASEK). Methods This retrospective study comprised 1020 consecutive eyes that had LASEK to correct myopia. MMC 0.02% was applied for 30 seconds over the ablated cornea in all cases. Due to the use of MMC, the programmed ablation was 10% less than the intended correction to avoid overcorrection. The relationship between preoperative spherical equivalent (SE) and the 3‐month postoperative SE was analyzed by lineal regression. We also compared the refractive result in the quartiles with the lowest and the highest preoperative myopia. Results Preoperatively, the mean SE was ‐5.29 ± 2.6 diopters (D). 3 months post‐op, the mean residual SE was +0.16 ± 0.4 D in the lowest quartile (≤ ‐3.25D) and ‐0.32 ± 0.8 D in the highest quartile (≥ ‐7D) (p=0.0001). The mean cylinder was ‐0.27 ± 0.4 D in the lowest quartile and ‐0.41 ± 0.5 D in the highest quartile (p= 0.003). There was a significant (p=0.0001, r2= 0.15) correlation between the preoperative and postoperative SE (i.e., the higher the preoperative SE, the greater the undercorrection). Conclusion MMC seems to influence the spherical refractive outcomes after myopic LASEK. Using a 10% fixed hypocorrection, LASEK with MMC tends to overcorrect low myopic defects and undercorrect high myopias.