目的:研究离体猪LASIK术中角膜板层刀片使用次数对角膜瓣厚度、均匀性和切削面的光滑程度的影响。方法:新鲜离体猪眼球36只,刀片使用1～6次分成Ⅰ～Ⅵ组,再将Ⅰ和Ⅱ,Ⅲ和Ⅳ,Ⅴ和Ⅵ合并为A,B,C组。测量6组猪眼球的角膜中央厚度、K值及眼压。在猪眼球上模拟角膜瓣的制作过程并计算角膜瓣中央厚度。从6组中各选取3只角膜瓣制成病理切片标本,在光学显微镜下观察角膜瓣厚度的均匀性。从Ⅰ,Ⅳ,Ⅵ组中各选取1只角膜瓣制成标本,在扫描电镜下观察角膜瓣切削面的光滑程度。结果:术前6组角膜瓣的平均角膜中央厚度、K值和眼压无差异。术后角膜瓣的平均厚度分别为152.7±14.6,143.8±9.3,128.3±12.7,114.2±9.6,99.7±5.7和70.0±12.7μm;除Ⅱ组与Ⅰ组无差异外,Ⅲ～Ⅵ组与Ⅰ组角膜瓣厚度均有差异。角膜瓣厚度与刀片使用次数呈负相关性。A,B,C3组角膜瓣的平均厚度分别为150.8±15.4,121.2±13.0和88.3±15.1μm,组间差异明显。随着刀片使用次数增多,角膜瓣厚度均匀性下降,角膜瓣切削面的光滑程度下降。结论:随着刀片使用次数的增多,角膜瓣厚度变薄,角膜瓣厚度的均匀性和角膜瓣切削面的光滑程度均下降。

AIM:To investigate influence used times of microke-ratome blades on corneal flap quality (including corneal flap thickness,uniformity of thickness and smoothness of cut surface) in LASIK through imitating the course that corneal flaps were made on freshly enucleated swine eyes.·METHODS:Thirty-six freshly enucleated swine eyes were divided into 6 groups(Ⅰ-Ⅵ) according to the times blades were used(1-6).Ⅰand Ⅱ,Ⅲ and Ⅳ,Ⅴ and Ⅵ were combined separately to A,B,C groups.Central corneal thickness,corneal refractive power and IOP were measured.The course that corneal flaps were made was imitated on enucleated swine eyes and central corneal flap thickness was calculated.3 flaps from every groups wew chosen and uniformity of corneal flap thickness was observed with optical microscopy.1 flap from three groups were chosen (Ⅰ,Ⅳ,Ⅳ)and smoothness of cut surface was observed with scanning electron microscopy.·RESULTS:There was no difference between the 6 groups in central corneal thickness、corneal refractive power and IOP before operation.The everage central corneal flap thickness of Ⅰ-Ⅵ group were 152.7±14.6,143.8±9.3,128.3±12.7,114.2±9.6,99.7±5.7,70.0±12.7μm.There was no difference between Ⅰand Ⅱ,but Ⅲ-Ⅵ were different from Ⅰin central corneal flap thickness.There was a negative correlation between corneal flap thickness and the used times of blades.The average corneal flap thickness of A-C were 150.8±15.4,121.2±13.0,88.3±15.1μm.There was significant difference between the two groups.With the increase in the used times of blades,uniformity of corneal flap thickness decreased with optical microscopy and smoothness of cut surface decreased with scanning electron microscopy.·CONCLUSION:With the increase in the used times of blades,corneal flap thickness became thinner,uniformity of corneal flap thickness and smoothness of cut surface decreased.

R779.63

中国辽宁省自然科学基金课题资助项目(No.20042081)~~