Corneal keratocyte apoptosis following topical intraoperative mitomycin C in rabbits.
OBJECTIVE
To determine the soaking duration and concentration effect of mitomycin C (MMC) on the corneal keratocyte following single intraoperative application.


METHODS
Two hundred ten pigmented rabbit eyes underwent mechanical epithelium debridement of the central 10-mm comea followed by soaking of six different solutions: MMC1A: 0.01% MMC x 1 minute; MMC1B: 0.01% MMC x 2 minutes; MMC2A: 0.02% MMC x 1 minute; MMC2B: 0.02% MMC x 2 minutes; BSS1: balanced salt solution (BSS) x 1 minute; and BSS2: BSS x 2 minutes. Thirty-five eyes were allocated into each group. Changes of the central comeal thickness, corneal clarity score, and keratocyte apoptosis were examined on days 0, 1, 2, 3, 5, 7, and 14.


RESULTS
A significant increase of central corneal thickness and corneal clarity score was noted in all MMC treated groups. The central corneal thickness recovered to its baseline level whereas the corneal clarity score remained increased at 2 weeks. The changes were more significant in MMC2 than in MMC1 corneas. However, changes of central corneal thickness and corneal clarity score were more significant in MMC1B than in MMC1A, whereas no difference was noted between MMC2A and MMC2B. Significantly higher stromal keratocyte loss and keratocyte apoptosis, from superficial to deep corneal stroma, was noted in MMC1 and MMC2 groups up to 14 days postoperatively, in a soaking duration and dose-dependent manner.


CONCLUSIONS
Single application of MMC on the corneal surface caused soaking concentration and duration dependent corneal edema and keratocyte apoptosis in this rabbit model.
Chang
Shu-Wen
SW
Department of Ophthalmology, Far Eastern Memorial Hospital, Ban-Chiao, Taiwan. swchang@mail.femh.org.tw
D000287:Administration, Topical; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015715:Corneal Edema / Q000139:chemically induced* / Q000473:pathology; D003318:Corneal Opacity / Q000139:chemically induced / Q000473:pathology; D003319:Corneal Stroma / Q000187:drug effects* / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects / Q000473:pathology; D007430:Intraoperative Care; D016685:Mitomycin / Q000633:toxicity*; D019384:Nucleic Acid Synthesis Inhibitors / Q000633:toxicity*; D011817:Rabbits; D013997:Time Factors
D019384:Nucleic Acid Synthesis Inhibitors; D016685:Mitomycin