PRK术后家兔角膜透射电镜、扫描电镜的实验研究

应用 SVS APEX PLUS型准分子激光治疗系统对 6只家兔双眼进行 PRK术 ,设定右眼- 4.0 0 D,左眼 - 8.0 0 D。分别于术后 3天、30天、1 0 0天两组随机选取 1只家兔 ,使其猝死摘除双眼球 ,取其角膜。每只角膜分为两半 ,一半角膜电镜下观察其超微结构 (1 /4行 SEM,1 /4行TEM)。透射电镜观察手术后 1 0 0天 ,角膜上皮细胞基本恢复正常。扫描电镜观察则上皮细胞界限分明 ,上皮明亮细胞较多 ,但微绒毛、微皱褶相对减少。提示 PRK术后 1 0 0天角膜组织结构基本正常 ,但仍有组织薄弱处和特殊性改变。其角膜上皮微绒毛、微皱褶相对减少 ,可能是临床上PRK术后部分患者近期角膜干燥的原因之一

Thestudy of TEM and SEM in the rabbit cornea after excimer laser photorefractive keratectomy

To evaluate the corneal healing of non equality diopter response ultrastructural after excimer laser photorefractive keratectomy (PRK) with SVS APEX PLUS excimer laser, PRK was operated on both eyes of 6 white rabbits (12 eyes).PRK was peformed on right eye of the rabbit for an attampted correction of -4.00 diopter,a nd performed on left eye of the rabbit for an attempted correction of -8.00 diopter.In 10d,30d and 100d the eyes were re examined repectively.The eyes of one rabbit were enucleated at random.Half of each cornea was prepared for transmission electron microscope(TEM) and scanning electron microscope(SEM) studing.TEM demonst ration in 100 d after PRK,the corneal epithelium returned to normal again.SEM demonstration in 100d after PRK,cornedepithelium was clear with more bright epithlium.Microplicae and mcrovilli were less than before.We found that despite recovery of acontinuous and smooth epithelial layer and near normal corneal tissues 100 d after PRK,abnormalities of both epithelium and superficial stroma could be detected in the area of ablation.The microplicae and microvilli of rabbit cornea epithelium became less after PRK,which could be one of reasons which cause ocular dry sensation in the same patients.