调整Kappa角及光学切削直径对准分子激光原位角膜磨镶术后的影响

目的评价调整光学切削直径及Kappa角后对准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后效果的影响。方法选取2017年1月至12月在我院行LASIK手术的高度近视患者313例(626眼),根据切削直径分成两组,试验组157例314眼,切削直径设定为6.0 mm,对照组156例312眼,切削直径设定为6.5 mm。试验组患者激光切削前修正Kappa角,对照组不做修正。患者术前进行裸眼视力、主视眼确定、验光、眼压、暗室下瞳孔直径、泪液分泌试验、裂隙灯、散瞳验光、眼底检查、pentacam测量角膜厚度、角膜地形图测量角膜前后表面及Kappa角等检查。术后1 d、1周、1个月随访,并检查裸眼视力、角膜厚度、波前像差及夜间视力、光晕、眩光等情况。比较两组患者角膜厚度变化、手术所用时间以及两组患者术后的高阶像差的差异。结果试验组与对照组患者年龄分别为18～44(24.19±5.33)岁、18～42(25.08±4.91)岁,屈光度分别为(-7.47±1.04)D、(-7.61±1.12)D。两组年龄、屈光度比较差异均无统计学意义(均为P>0.05)。试验组与对照组患者术前Kappa角分别为,X轴:(210±40)μm、(200±30)μm,Y轴:(190±30)μm、(220±40)μm,差异无统计学意义(P=0.210)。两组手术前后的角膜厚度及术后角膜基质床的厚度差异均无统计学意义(均为P>0.05)。试验组与对照组的手术时间分别为(15.56±1.89)s和(20.83±3.03)s,差异有统计学意义(P=0.000)。试验组的总高阶像差和垂直慧差的变化均明显低于对照组(均为P<0.01),但两组间的水平慧差差异无统计学意义(P>0.05),对照组的球差低于试验组(P<0.01)。结论 LASIK手术中科学合理地调整Kappa角可有助于提高患者术后的视觉质量。

Effects of adjusted optical zone ablation diameter with optimized Kappa angle on LASIK surgery

Objective　To evaluate the effect of adjusting the optical ablation diameter and Kappa angle on the outcome of LASIK.Methods　A total of 313 patients (626 eyes) with high myopia who underwent LASIK in our hospital from January 2017 to December 2017 were enrolled，and according to ablation diameter，the patients were divided into two groups:experimental group (157 patients，314 eyes) received LASIK with a narrowedoptical zone of 6.0 mm，and control group (156 patients，312 eyes) received a routine LASIK with an optical zone of 6.5 mm.Kappa angle was corrected before laser cutting in the experimental group，which was not performed in the control group.Uncorrected visual acuity，determination of dominant eye，optometry，intraocular pressure，diameter of pupil under dark chamber，tear secretion test，slit lamp，mydriasis optometry，fundus examination，pentacam measurement of corneal thickness and corneal topography were performed before operation.The uncorrected visual acuity，corneal thickness，wavefront aberration，night visual acuity，halo and glare were examined at 1 day，1 week and 1 month after operation.The changes of corneal thickness，the time of operation and the difference in higher-order aberrations between the two groups were compared.Results　The patients in the experimental group and the control group were 18-44 (24.19±5.33) years old，18-42 (25.08±4.91) years old，respectively，and the average diopter equivalent spherical mirror was (-7.47±1.04)D，(-7.61±1.12)D，respectively.There was no statistically significant difference in age and diopter between the two groups (both P>0.05).The Kappa angles of the experimental group and control group were (210±40)μm，and (200±30)μm at X-axis，(190±30)μm and (220±40)μm at Y-axis，respectively，with no statistical difference (P=0.210).There was no significant difference in corneal thickness and thickness of the postoperative corneal stromal bed between the two groups (all P>0.05).However，the time spent on surgery of the experimental group ［(15.56±1.89)s］ and the control group ［(20.83±3.03)s］ was statistically significant (P=0.000).The total high-order aberration and vertical coma of the experimental group were significantly lower than those of the control group (both P<0.01)，but there was no significant difference in the horizontal coma between the two groups(P>0.05).The spherical aberration of the control group was lower than that of the experimental group (P<0.01).Conclusion　Reasonable corrected Kappa angle in LASIK surgery can be adopted to benefit patients’ visual quality.