方法：选取接受准分子激光高度近视矫正术的连续性病例60例120眼。术前等效球镜值为-6.00～-9.00(平均-7.20±1.18)D。术前平均角膜厚度511±17.93μm。观察术前及术后1，3，6mo裸眼及最佳矫正视力、剩余角膜厚度、屈光度、角膜地形图形态、模拟角膜曲率计度数(Simk)、角膜不规则指数(CIM)、角膜形态因子(SF)的变化。

结果：术后1，3，6mo的裸眼视力>1.0的百分比构成分别为96%，97%，98%，屈光度较术前明显改善且在术后6mo基本稳定。术后1，3，6mo角膜地形图平滑型分别占86%，93%，96%。其他类型较少，无中央岛形成，切削形态随时间延长逐渐规则，6mo后基本稳定。术后1，3，6mo与术前相比，术后Simk的等效值、Simk差值明显减小，CIM明显增高，SF向负值改变，其差异有统计学意义(P<0.05)，手术切削角膜厚度节约为30±12.11μm。

结论： TOSCA是治疗薄角膜高度近视的有效手术，术后角膜地形图检查和分析能清晰的显示角膜表面形态的变化，有利于实施个体化的准分子激光手术而获得最完美的视功能。

METHODS: Totally 60 patients(120 eyes)with high myopia received corneal refractive surgery. Preoperative spherical equivalent of patients was from -6.00D to -9.00D, and the mean was -7.20±1.18D, the mean corneal thickness was 511±17.93μm. Then the uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), residual corneal thickness, diopter, corneal topography, simulated keratoscope reading(SIMK), corneal irregularity measurement(CIM), and shapa factor(SF)were examined preoperatively and 1 month, 3 and 6 months postoperatively.

RESULTS: The percentage of UCVA exceeding and being equal to 1.0 at 1 month, 3, 6 months after TOSCA was 96%, 97%, 98%. The diopter after TOSCA was improved evidently and turned to be stable at 6 months. The percentage of corneal topographic pattem after 1 month, 3 and 6 months including smooth pattem was 86%,93%,96% respectively while was relatively stable, and other pattem was seldom. No central islet was fond. Other rectomy shape became regulating gradually. At 1 month, 3 and 6 months post-operation, Simk equivalent value and Simk difference value decreased significantly, and the value of corneal irregularity measurement(CIM)increased too. While the value of corneal shape factor changed to negative direction. These above mentioned parameters showed statistically significant difference compared with those of pre-operation(P<0.05).

CONCLUSION: Examination and analysis on the cornmeal topography before and after TOSCA can clearly display the morphological change of the corneal surface topography and morphology, which helps carry out TOSCA individually and achieve perfect correction.