丝裂霉素C对准分子激光屈光性角膜切削术后角膜混浊的实验研究

目的探讨丝裂霉素Ｃ对准分子激光屈光性角膜切削术后角膜上皮下雾状混浊（ｈａｚｅ）的影响。方法对４５只新西兰白兔的双眼行准分子激光屈光性角膜切削术,术中、术后分别给予０．００８％丝裂霉素Ｃ、０．１％地塞米松治疗及空白对照。术后分别进行裂隙灯、角膜内皮镜、光镜和透射电镜检查。结果术后４及８周,丝裂霉素Ｃ组角膜ｈａｚｅ轻于对照组和地塞米松组;地塞米松组轻于对照组。术后１、４及８周,丝裂霉素Ｃ组术区前基质内角膜细胞数较对照组和地塞米松组少,后两组间差异不明显。三组间角膜上皮愈合时间、角膜上皮厚度及内皮细胞密度差异无显著性（Ｐ＞０．０５）。结论丝裂霉素Ｃ能通过抑制角膜细胞的生长而减轻ｈａｚｅ的形成,其效果优于地塞米松,且无明显副作用,是一种较理想的抑制ｈａｚｅ形成的药物

Effects of mitomycin C on haze after photorefractive keratectomy for myopia in rabbits

Objective To investigate the effects of mitomycin C on haze after photorefractive keratectomy. Methods Forty five rabbits underwent bilateral 193 nm excimer laser photorefractive keratectomy to correct 8 diopters of myopia. All eyes were allocated randomly to be treated with 0.008% mitomycin C during operation, or 0.1% dexamethasone after operation, or no medical treatment as control. Clinical and histopathologic examinations were made with slit lamp microscope, specular microscope, light microscope and transmission electron microscope. Results At 4, 8 weeks after operation, the corneal haze was significantly less in mitomycin C group than that in the control group or in dexamethasone group, and the corneal haze was significantly less in dexamethasone group than that in the control group. At 1, 4, 8 weeks, the number of keratocyte in the anterior stroma of ablation area was significantly less in mitomycin C group than in the cortrol group or in dexamethasone group. The difference between dexamethasone group and the control group was insignificant. The changes in time of reepithelialization, thickness of epithelium and keratocyte number of anterior stroma in ablation area were statistically insignificant among all groups. Conclusion Mitomycin C can reduce corneal haze by inhibiting the proliferation of keratocyte and has no toxicity on cornea. Mitomycin C is more effective than dexamethasone on haze.