To investigate the combined effects of ethanol and mitomycin C (MMC) application on the corneal stroma of rabbits that underwent photorefractive keratectomy (PRK).METHODS
Twenty-four rabbits (24 eyes) underwent PRK to correct −9.00 diopters of myopia. Twelve eyes had ethanol application before removing the epithelium and 12 eyes had the epithelium manually removed without ethanol. Eyes in both groups had topical MMC 0.02% application for 12 seconds immediately after excimer laser ablation. Twelve rabbits were sacrificed at two time points—4 hours and 4 weeks after surgery— and immunohistochemistry was performed with TUNEL assay, alpha-smooth muscle actin (alpha-SMA), and DAPI.RESULTS
More TUNEL-positive cells were observed in the ethanol-treated group compared to the mechanical debridement group at 4 hours after surgery (P<.01). No significant difference in alpha-SMA-positive cells was detected between the two groups at 4 weeks after sugery. However, decreased keratocyte density in the anterior stroma was more pronounced in the ethanol-treated group compared to the mechanical debridement group (P<.02).CONCLUSIONS
Ethanol application for epithelial removal during PRK seems to produce a synergistic effect with MMC, resulting in fewer keratocytes in the anterior stroma of rabbit corneas treated with MMC and ethanol than in corneas treated with MMC alone after PRK.