WaveLight FS200飞秒激光角膜瓣瞳孔中心偏离与术后疗效的关系

Relationship between the offset of a laser-assisted flap using the WaveLight FS200 femtosecond laser and the clinical results

目的探讨WaveLight FS200飞秒角膜瓣瞳孔中心偏离与飞秒激光辅助制瓣的准分子激光角膜原位磨镶术(FS-LASIK)术后疗效的关系。方法采用队列研究方法,纳入2017年6月至2018年7月在中山大学附属东华医院眼科中心应用Wavelight FS200进行FS-LASIK治疗近视的患者125例125眼,依据飞秒激光制作的角膜瓣是否偏离瞳孔中心分成无偏离组57眼和偏离组68眼,2个组年龄、性别构成比、裸眼视力(UCVA)、球镜度、中央角膜厚度(CCT)的基线资料匹配,差异均无统计学意义(均P>0.05)。追踪观察2个组术后1周、1个月的UCVA、散光、球镜度、角膜曲率及高阶像差情况。结果术后1周和1个月,2个组视力、角膜曲率、残留球镜度数及球差、彗差比较,差异均无统计学意义(均P>0.05);术后1周,无偏离组≤-0.50 D和>-0.50 D的眼数分别占87.7%(50/57)和12.3%(7/57),偏离组≤-0.5 D和>-0.5 D的眼数分别占73.5%(50/68)和26.5%(18/68),2个组间不同散光度数眼数分布比较,差异有统计学意义(χ2=3.902,P=0.048);术后1个月,2个组间不同散光度数眼数分布比较差异无统计学意义(χ2=2.031,P=0.068)。术后1周和1个月,无偏离组的三叶草差分别为0.05(0.04,0.08)和0.05(0.03,0.07),均低于偏离组的0.06(0.04,0.10)和0.06(0.05,0.09),差异均有统计学意义(Z=-2.245,P=0.022;Z=-2.370,P=0.018);术后1周和1个月,2个组球差和彗差比较差异均无统计学意义(均P>0.05)。结论Wavelight FS200飞秒激光制作角膜瓣过程中的瞳孔中心偏离对于远期视力及散光等视觉质量未发现有意义的影响,术后早期散光及部分高阶像差可能会影响患者术后早期视觉体验。

Objective To evaluate the relationship between the offset of a laser-assisted flap using the WaveLight FS200 femtosecond laser and the clinical results after femtosecond laser-assisted laser in situ keratomileusis(FS-LASIK).Methods In this prospective cohort study,125 patients who underwent FS-LASIK for myopia by WaveLight FS200 femtosecond laser from June 2017 to July 2018 at the Tungwah Ophthalmic Center were divided into two groups according to the offset of the corneal flap from the pupil center:the no-offset group(57 eyes)and the certain-offset group(68 eyes);the baseline data,including age,sex,uncorrected visual acuity(UCVA),spherical degree,and central corneal thickness were matched in the two groups.UCVA,residual astigmatism,spherical degree,corneal curvature and aberration were observed 1 week and 1 month after surgery.The study protocol was approved by the Ethics Committee of Tungwah Hospital of Sun Yat-Sen University(No.2017DHLL004).Written informed consent was obtained from each subject prior to entering the study cohort.Results UCVA,corneal curvature,spherical degree,spherical and corneal aberration between the two groups were not significantly different(all at P>0.05).One week after surgery,the residual astigmatism was≤-0.50 D in 50 eyes(87.7%,50/57)and>-0.50 D in 7 eyes(12.3%,7/57)in the no-offset group;the residual astigmatism was≤-0.50 D in 50 eyes(73.5%,50/68)and>-0.50 D in 18 eyes(26.5%,18/68)in the no-offset group.The residual astigmatism between the two groups 1 week after surgery was significantly different(χ2=3.902,P=0.048),and there was no significant difference in residual astigmatism 1 month after surgery(χ2=2.031,P=0.068).The trefoil of the no-offset group was statistically less than of the certain-offset group at 1 week and 1 month after surgery(0.05[0.04,0.08]vs.0.06[0.04,0.10];0.05[0.03,0.07]vs.0.06[0.05,0.09])(Z=-2.245,P=0.022;Z=-2.370,P=0.018).The spherical aberration and coma were not significantly different between the two groups at 1 week and 1 month after surgery(both at P>0.05).Conclusions The offset from femtosecond laser-assisted flap by WaveLight FS200 has no effect on long-term visual acuity or residual astigmatism.Some patients may have different visual experiences because of the residual astigmatism and higher order aberration during the early postoperative stage.