自制羊膜提取液在兔眼准分子激光屈光性角膜切削术后的应用研究

Application of Self-made Amniotic Membrane Extraction in Rabbits after Photorefractive Keratectomy

目的:探讨自制羊膜提取液对兔眼准分子激光屈光性角膜切削术(photorefractive keratectomy,PRK)后角膜上皮下雾状混浊(Haze)的影响。方法:常规方法获取新鲜健康人羊膜,保留上皮细胞,反复冻融、过滤,获得羊膜匀浆液,室温下保存备用。选择健康新西兰大白兔27只,在相同条件下,双眼行PRK,术后实验动物随机分为实验组、对照组、空白组,每组9只兔,18只眼。术后双眼给予局部抗生素眼药水,术后48 h实验组滴用羊膜提取液,对照组用0.1%磷酸地塞米松眼液,空白组用不含羊膜提取液的赋形剂。分别于术后1、2、4、8周记录角膜Haze情况并按Fantes等级标准进行评分,行眼前节照相记录Haze的形态。随机每组选择3只兔作为病理观察用,分别于术后1、4、8周各处死1只,摘除眼球做病理切片检查,观察术区角膜、炎症细胞及成纤维细胞情况。结果:PRK术后早期,3组动物角膜荧光素钠染色均为阳性,但多数角膜上皮缺损均在术后3d修复。PRK术后Haze的发生率为100%,所有术眼均在术后1周左右开始出现程度不同的Haze,术后4周时Haze尤其明显,直至术后8周。实验组和对照组角膜Haze形成程度相似,且明显低于空白组,差异有统计学意义(P<0.05)。结论:羊膜提取液具有促进兔角膜上皮修复的作用,并能减少PRK术后兔Haze的形成。

Objective： To establish the model of photorefractive keratectomy（ PRK） in rabbits,and to investigate the effect of self-made amniotic membrane extraction on corneal fog opacity（ Haze） after PRK. Methods： The healthy human amniotic membrane was prepared according to the routine reference,epithelial cell was reserved,and to freeze thawing repeatedly and filter to obtain amniotic membrane extraction,then stored at the room temperature. A total of 54 eyes of 27 New Zealand white rabbits were operated by PRK in the same condition. All of the rabbits were randomly divided into experimental group,control group and blank group. There were 18 eyes of 9 rabbits in each group. Antibiotic eye drops were given for each group＇s rabbits after PRK. Amniotic membrane extraction were given for experimental group＇s rabbits,0. 1% dexamethasone phosphate eye drops were given for control group＇s rabbits and diluents bases without amniotic membrane extraction were given for blank group＇s rabbits 48 h later. Postoperative clinical examine was done everyday. The Haze information was measured as the Fantes standard at 1,2,4,8 weeks. And 3 rabbits were selected randomly from each group for the pathologic examination,1 rabbit was killed in each group at 1,4,8 weeks after operation and extirpated the eyeball for pathologic observation,the information of the cornea,inflammatory cells and desmocyte were observed. Results： In the earlier period after PRK,the staining of cornea with fluorescein sodium in 3 groups were positive,but most of the corneal epithelium defection were repaired at 3 days after PRK. The incidence rate of Haze was 100% after PRK,all the eyes started to appear the Haze in 1 week after opertion,especially from 4 weeks to 8weeks were severe. The degree of Haze in experimental group and control group were obviously less than the degree of Haze in blank group after operation（ P〈0. 05）. Conclusion： Amniotic membrane extraction has the role of promoting corneal epithelium recover,and can reduce the degree of Haze after PRK in rabbits.