准分子激光上皮下角膜磨镶术(LASEK)与准分子激光角膜切削术(PRK)术后兔角膜超微结构实验研究

The study of ultrastructure in wound healing of rabbits cornea after laser epithelial keratomileusis and photorefractive keratectomy

目的:比较准分子激光上皮下角膜磨镶术(LASEK)与准分子激光角膜切削术(PRK)术后兔角膜创面愈合的情况,从组织学超微结构角度探讨角膜雾状混浊(Haze)及屈光度数回退的可能成因。方法:5 2只新西兰白兔分为8组,每只兔右眼行LASEK ,左眼行PRK。术后1天、7天及1、3、4、5、6月处死动物取角膜行透射电镜和扫描电镜观察,比较术后每一时相点角膜上皮及角膜基质愈合的动态变化过程。结果:LASEK术后角膜上皮细胞、基底膜、基质内胶原纤维和成纤维细胞的超微结构改变程度轻于PRK组。结论:术后LASEK组角膜创伤修复反应弱于PRK ,这可能是LASEK术后角膜恢复正常较早的原因。

Objective: To observe and compare the wound healing processes of the rabbit cornea wihch underwent LASEK or PRK and to investigate the possible mechanism of corneal haze and myopic regression.Methods New Zealand White rabbits were divided into 8 groups:normal control group(n=6),1 day ,7 days,1,3,4,5 and 6 month groups(n=14).Every rabbit underwent LASEK in one eye while the other one with PRK.We use transmission and scanning electron microscope to compare the wound healing prcess of corneal epithelium and its basement in rabbit cornea of every time point.The results were analysised with image and data analysis software.Result:The ultrastructure changes of corneal epithelium,epithelial basement,collagen and fibroblast cell after LASEK were much less than PRK.Conclusions:There are less morphological changes of ultrastucture of cornea epithelium,basement membrane,collagen and fibroblasts.