A Prospective Evaluation of the Effect of Mitomycin-C on Corneal Endothelium after Photorefractive Keratectomy for Myopia Correction

PURPOSE: The aim of the study was to assess the effect of mitomycin-C (MMC) 0.02% application on corneal endothelium in patients undergoing photorefractive keratectomy (PRK) for the correction of myopia and compound myopic astigmatism. METHODS: A prospective observational study including patients with myopia who underwent PRK plus intraoperative application of MMC 0.02%. All patients underwent noncontact specular microscopy preoperatively and 6 months postoperatively. The following parameters were analyzed: mean cell area (MCA), central corneal endothelial cell density (ECD), and coefficient of variation (CV) in cell size. RESULTS: One hundred and thirty-nine eyes of 73 patients with a mean age of 24.95 ± 3.23 years were included in the study. Mean baseline preoperative pachymetry was 519.54 ± 28.62 μm. The mean preoperative spherical equivalent was −4.6 ± 2.3D (range from −1D to −10D) which decreased to mean postoperative spherical equivalent of −0.125 ± 0.32D. Mean baseline ECD was 2829.3 ± 188.8 cells/mm(2), MCA was 354.6 ± 24.9 μm(2)/cell, CV was 0.35 ± 0.06, and hexagonality was 50.1 ± 6.64. The mean ECD decreased by 43 ± 1.6 cells/mm(2) which was not statistically significant (P = 0.07). The MCA increased by 5 ± 1.3 μm(2)/cell, but this was not statistically significant (P = 0.07). However, both the CV and percentage of hexagonal cells showed statistically significant differences in the median values as compared to preoperatively (P < 0.001). CONCLUSION: In our study, MMC had no significant effect on corneal endothelial cell counts or MCA. While there were statistically reduced CV and percentage of hexagonal cells, these did not appear to be clinically significant. MMC is safe to use routinely to prevent haze formation in PRK.