角膜地形图引导与波前像差优化的飞秒LASIK术后角膜地形图比较

目的 评估角膜地形图引导的飞秒激光制瓣的准分子激光原位角膜磨镶术（FS-LASIK）与波前像差优化的FS-LASIK治疗近视散光术后临床效果、角膜地形图的变化及角膜像差的差异。方法 前瞻性队列研究。将44例（87眼）近视散光患者根据接受的手术方式不同分成2组：Topography组（角膜地形图引导的个性化FS-LASIK，22例44眼）及Wavefront组（波前像差优化的FS-LASIK，22例43眼）。Topography组应用Wavelight Topolyzer角膜地形图仪采集角膜地形图数据。术后6个月，对2组视力、屈光度、角膜不规则指数、激光切削的居中性及角膜波前像差采用独立样本t检验进行比较。结果 术后6个月，2组间裸眼视力（UCVA）及最佳矫正视力（BCVA）的差异均无统计学意义，无一例出现术后BCVA低于术前。术后2组间球镜度、柱镜度及等效球镜度差异亦无统计学意义。Topography组患者术后角膜表面变异指数（ISV）（39.9±13.0）低于Wavefront组（44.9±12.2），差异有统计学意义（t=-2.296，P<0.05），2组术后ISV均较术前增加（t=5.216、7.870，P<0.05）。Topography组患者术后平均切削偏心量[（0.24±0.29）mm]低于Wavefront组[（0.29±0.31）mm]，但2组间差异无统计学意义（t=-1.005，P>0.05）。术后6个月，Topography组角膜水平彗差（Z31）及球差（Z40）[（-0.166±0.357）μm和（0.390±0.263）μm]均低于Wavefront组[（-0.362±0.353）μm和（0.486±0.164）μm]，差异有统计学意义（t=2.325、-2.096，P<0.05）。结论 角膜地形图引导的FS-LASIK与波前像差优化的FS-LASIK相比较同样安全有效，但前者术后角膜表面规则性更好，引入的角膜高阶像差更低。

Comparison of corneal topography after topography-guided FS-LASIK and wavefront-optimized FS-LASIK

Objective To compare the outcomes of topography-guided LASIK and wavefront-optimized LASIK in eyes of patients undergoing femtosecond laser LASIK (FS-LASIK) for myopia with astigmatism.Methods In this prospective clinical study,44 eyes of 22 patients underwent topography-guided LASIK (topography group) and 43 eyes of 22 patients underwent wavefront-optimized LASIK (wavefront group).The topography treatment was based on data generated by a networked diagnostic device:Wavelight Topolyzer.Visual acuity,refractive error,the index of corneal surface variance (ISV),corneal wavefront aberrations and ablation decentration were evaluated 6 months postoperatively.Data were analyzed using independent t test.Results Six months postoperatively,there were no significant differences in UCVA or BCVA (t=-1.553,-1.570,P＞0.05) between the groups.No eyes lost a line of BCVA in either group.There were no statistically significant differences in postoperative average sphere,cylinder refraction or spherical equivalent (SE) between the groups.The postoperative value of ISV increased compared to baseline for both groups (t=5.216,7.870,P＜0.05).The mean postoperative ISV in the topography group (39.9±13.0) was significantly lower than that in the wavefront group (44.9±12.2) (t=-2.296,P＜0.05).The postoperative mean decentration in the topography group (0.24± 0.29 mm) was less than that in the wavefront group (0.29±±0.31 mm),but the difference was not statistically significant (t=-1.005,P＞0.05).There were significant differences in postoperative coma aberrations (Z31) [-0.166 ±0.357 m vs.-0.362±±0.353 m,t=2.325,P＜0.05] and spherical aberrations (Z40) [0.390± 0.263 μm vs.0.486±±0.164 μm,t=-2.096,P＜0.05] between the two groups.Conclusion Both topography-guided ablation and wavefront-optimized ablation provide good visual acuity and refractive results,but the former treatment results in a better index of corneal surface variance and induces fewer corneal aberrations.