角膜塑型术前后的角膜地形图分析

分析角膜塑型术后角膜地形图的类型及其动态变化 ,探讨角膜地形图类型与视力的关系。方法 :应用角膜地形图仪对比分析了 36 0例 ( 712眼 )戴OK镜前后角膜表面的形态及与视力的关系。结果 :术前角膜地形图以蝴蝶结型为多 ( 78 6 % ) ;术后角膜地形图分为两类八型 ,即规则型 (均匀型 ,顺轴圆枕型 ,逆轴圆枕型 ,局灶型地形图改变 )和不规则型 (中央岛型 ,半环型 ,钥匙孔型 ,不规则型 ) ,以均匀型和圆枕型占多数 ,各型随时间而改变 ,且趋于平稳。不规则地形图对术后最佳矫正视力的影响较大。结论 :角膜地形图的定量分析对角膜塑型术后角膜表面性状的评价 ,镜片设计的改进 ,塑型疗效的预测等有重要的意义。

Corneal topography before and after orthokeratology therapy

Objective:To study the changes in corneal surface morphology before and after orthokeratology and analyze the decentralization of the treatment. Methods:Corneal topography was examined on 712 eyes of 360 cases with myopia with computer assisted photokeratography before and after orthokeratology(OK). Results:Before OK the corneal topography of most examined eyes(78 6%)was symmetric bow tie pattern or asymmetric bow tie pattern;the corneal topography of the treated regions was mainly round or approximately rounds(64 48%).The more was the distance of decentralization,the more was the increasing of postoperative corneal astigmatism and also the more was the decreasing of the best corrected visual acuity. Conclusions:Examination and analysis on the corneal topography before and after OK may clearly display the changes in the corneal surface morphology,and quantitatively evaluate the decentralization.