SMILE术后屈光状态偏差原因分析

An Analysis of Postoperative Spherical Equivalent Deviation after Small Incision Lenticule Extraction

目的:探讨飞秒激光小切口角膜基质透镜取出术(SMILE)后屈光状态偏差的原因,为Nomogram值的个性化设定提供参考。方法:回顾性系列病例研究。选择2019年1月至2020年4月在北京大学深圳医院接受SMILE且术后随访时间为3个月的近视患者200例(400眼)。收集患者年龄、术前等效球镜度(SE)、术前平均角膜曲率(Km)及术后1周、1个月、3个月的SE等数据。根据术前SE分为低度近视组(≥-3.00 D)、中度近视组(>-6.00~<-3.00 D)、高度近视组(≤-6.00 D);根据术前Km分为低曲率组(≤42 D)、中曲率组(>42~<45 D)、高曲率组(≥45 D)。手术前后SE比较采用Kruskal Wallis H检验或单因素方差分析,同一患者不同眼别比较采用Wilcoxon秩和检验或配对t检验进行统计学分析。患者主视眼不同时间段各SE的相关分析采用Spearman相关分析和多元线性回归分析。结果:术后1周SE与Km、Nomogram值、术前SE呈负相关(r=-0.115,P=0.029;r=-0.174,P=0.014;r=-0.170,P=0.016);术后1个月SE与Nomogram值、年龄、术前SE呈负相关(r=-0.225,P=0.002;r=-0.148,P=0.046;r=-0.203,P=0.006),术后3个月SE与Nomogram值(r=-0.338,P=0.002)、术前SE(r=-0.336,P=0.002)呈负相关。进一步回归分析示Km(B=-0.033,P=0.047)、术前SE(B=-0.037,P=0.017)是术后1周SE的影响因素;年龄(B=-0.013,P=0.022)、Nomogram值(B=-0.564,P=0.001)是术后1个月SE的影响因素;术前SE是术后3个月SE的影响因素(B=-0.070,P=0.001)。低、中、高度近视组间术后1周(H=6.007,P=0.05)、术后1个月(H=6.236,P=0.044)、术后3个月(H=6.051,P=0.004)的SE比较差异均有统计学意义。左右眼别间术后1周(Z=-3.327,P=0.001)、术后1个月(Z=-3.130,P=0.002)的SE比较差异均有统计学意义,术后3个月SE差异无统计学意义。结论:年龄越大及高度近视患者术后屈光状态越趋向于近视,呈欠矫现象;年龄越小及低度近视患者术后屈光状态越趋向于远视,呈过矫现象。年龄、术前SE是术后屈光状态的影响因素,在手术设计时应根据影响因素个体化设定Nomogram值以达最大手术疗效。

Objective:To observe refractive status after femtosecond laser small incision lenticule extraction(SMILE);to explore the causes of postoperative spherical equivalent deviation.Methods:Retrospective case series study.A total of 200 patients(400 eyes)who had undergone SMILE surgery in Peking University Shenzhen Hospital from January 2019 to April 2020 were observed at the 3-month follow-up.Parameters like age,preoperative spherical equivalent(SE),preoperative mean keratometry(Km)and postoperative SE at 1 week,1 month,3 months were collected.Patients were divided into 3 groups according to preoperative SE:Low myopia group(≥-3.00 D),moderate myopia group(>-6.00-<-3.00 D),high myopia group(≤-6.00 D),and divided into three groups according to preoperative Km:Low curvature group(≤42 D),moderate curvature group(>42-<45 D),high curvature group(≥45 D).At 1 week,1 month,and 3 months postoperatively,a Kruskal Wallis test or ANOVA was used to compare the postoperative SE in each group.A Wilcoxon test or paired-samples t test was used to compare the postoperative SE among the two groups divided according to the dominant eye and right/left eyes.The parameters from dominant eyes were analyzed by Spearman correlation coefficient and multiple linear regression.Results:The postoperative SE was negatively correlated with Km,nomogram values and preoperative SE at 1 week postoperatively(r=-0.155,P=0.029;r=-0.174,P=0.014;r=-0.170,P=0.016),and negatively correlated with nomogram values,age and preoperative SE at 1 month postoperatively(r=-0.225,P=0.002;r=-0.148,P=0.046;r=-0.203,P=0.006).The nomogram value(r=-0.338,P=0.002)and preoperative SE(r=-0.336,P=0.002)were negatively correlated with SE 3 months postoperatively.Regression analysis showed that Km(B=-0.033,P=0.047)and preoperative SE(B=-0.037,P=0.017)are the influence factors of postoperative SE at 1 week.Age(B=-0.013,P=0.022)and nomogram value(B=-0.564,P=0.001)are the influence factors of postoperative SE at 1 month.Preoperative SE is the influence factor of postoperative SE at 3 months(B=-0.070,P=0.001).Comparison of the SE between the low,moderate and high myopia groups 1 week(H=6.007,P=0.05),1 month(H=6.236,P=0.044)and 3 months(H=6.051,P=0.004)postoperatively showed statistically significant differences.The difference in postoperative SE between the right and left eyes was statistically significant at 1 week(Z=-3.327,P=0.001)and 1 month(Z=-3.130,P=0.002)postoperatively but not statistically significant at 3 months.Conclusions:The older and high myopia patients'postoperative refractive status tends to be myopic,meaning undercorrection.The younger and low myopia patients'postoperative refractive status tends to be hyperopic,meaning overcorrection.Postoperative refractive status is influenced by age and preoperative SE.Nomogram is characteristically set according to the influence factors to achieve the maximum surgical effect.