Histopathologic Changes Induced by Topical Mitomycin-C in Rabbit Corneas

To evaluate histopathological changes induced by 0.02% mitomycin-C (MMC) in rabbits corneas. This study was performed on 48 corneas of 24 rabbits (Dutch type, Albino). Under general anesthesia, lamellar keratectomy was performed and either MMC 0.02 % (MMC group) or balanced salt solution (control group) was applied to the stromal bed for one minute. Sixty days later, light microscopic examination was performed on corneal buttons after authentication, corneal tissue fixation and staining with Hematoxylin-Eosin, periodic acid Schiff and Congo red as needed. One of the MMC cases showed decreased keratocyte count. Other findings such as interface scaring, keloid formation, stromal interface vascularization, stromal and flap edema, epithelial hyperplasia over the incision and flap occurred with the same frequency in MMC and control groups. Stromal scaring was less in the MMC group (zero vs two). There was faint eosinophilic staining in the interface in two and epithelial thinning over the flap in eyes of the control group. The endothelium was normal in all samples. Application of MMC 0.02% to the stromal interface in rabbit corneas led to decreased stromal keratocyte count and fibrosis but apparently had no adverse effect on interface healing, epithelial cell regeneration and the endothelium.