高度近视LASIK术后远期屈光回退的相关因素分析

Analysis of correlation factors in refractive regression after LASIK of high myopia

目的探讨高度近视准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后远期屈光回退的各种可能影响因素。方法 96例(167眼)高度近视患者(术前SE-6.00^-10.00D),随访5~6a,对其中发生屈光回退的37眼和未发生屈光回退的130眼术前及术后5a的随访资料进行对比,检测LASIK术后不同时期的屈光度和屈光回退率;进行屈光回退单因素分析和多因素分析。结果 LASIK术后1d、1个月、3个月、6个月、1a、5a SE分别为(-0.08±0.31)D、(-0.09±0.32)D、(-0.15±0.47)D、(-0.15±0.46)D、(-0.21±0.51)D、(-0.55±0.80)D,均小于术前(P=0.000);术后不同时期屈光回退率分别为0、1.20%、2.40%、3.59%、5.40%、22.16%;屈光回退单因素分析结果显示:产生5个对屈光回退有意义的变量:(1)术前SE(P=0.003);(2)术前CCT(P=0.018);(3)术前与术后5a CCT变化值(术前CCT-术后5a CCT)(P=0.009);(4)术前与术后5a角膜曲率变化值(术前角膜曲率-术后5a角膜曲率)(P=0.019);(5)术中角膜中心切削直径(P=0.001)。屈光回退多因素分析:产生4个对屈光回退有意义的变量:术前SE高、术前与术后5a角膜曲率变化值小、术前与术后5a CCT小、术中角膜中心切削直径小者术后易出现屈光回退。它们对屈光回退的影响作用(标准回归系数的绝对值大者易出现屈光回退)从大到小依次为:术前SE|-0.581|>术前与术后5a角膜曲率变化值|-0.370|>术前与术后5a CCT变化值|-0.302|>术中角膜中心切削直径|-0.231|。结论 LASIK可有效治疗-6.00^-10.00D的近视。术前SE高、术前与术后角膜曲率变化值小、术前与术后CCT变化值小、术中角膜中心切削直径小者术后易出现屈光回退。手术技术和激光治疗的不断改进,将有助于提高LASIK的预测性,避免屈光回退现象发生。

Objective To investigate various factors of refractive regression at long term in high myopic patients who underwent laser in situ keratomileusis（LASIK）over five years.Methods The study was a retrospective analysis of 167 eyes of 96 patients who had undergone LASIK with preoperative refraction ranging from-6.00 D to-10.00 D.All patients were followed up for 5 to 6 years.We compared the preoperative and postoperative clinical data between 37 eyes with regression and 130 eyes without regression and investigated the relationship between refractive regression and various factors such as age,gender,intraocular pressure,preoperative refraction,corneal curvature,corneal thickness,laser ablation diameter,ocular axis length,and so on.Results At 1 day,1 month,3 months,6 months and 1 year after LASIK,SE were（-0.08±0.31）D,（-0.09±0.32）D,（-0.15±0.47）D,（-0.15±0.46）D,（-0.21±0.51）D and（-0.55±0.80）D,respectively,which were all lower than that before LASIK（all P=0.000）.Rates of refractive regression were 0,1.20%,2.40%,3.59%,5.40%,22.16% at different time points after LASIK.Univariate analysis of refractive regression showed there were five factors related to refractive regression：（1）The preoperative spherical equivalent（P=0.0030.01）;（2）The preoperative CCT（P=0.0180.05）;（3）The amount of change in preoperative and postoperative 5 a CCT（P=0.0090.05）;（4）The amount of change in preoperative and postoperative 5 a corneal curvature（preoperative corneal curvature-postoperaive 5 a corneal curvature）（P=0.0190.05）;（5）The laser ablation diameter（P=0.0010.05）.Multivariate analysis of refractive refression showed that there were four significant factors related to refractive regression：Preoperative higher spherical equivalent,lower amount of change in preoperative and postoperative 5 a CCT,less preoperative and postoperative 5 a CCT,less intraoperative laser ablation diameter regression is easy to have refractive regression.Moreover,according to the size of absolute value of their standard regression coefficient,their importance to regression were in turn to preoperative spherical equivalent refraction｜-0.581 ｜ the amount of change in preoperative and postoperative corneal curvature ｜-0.370｜the amount of change in preoperative and postoperative CCT ｜-0.302｜ the laser ablation diameter｜-0.231｜.Conclusions LASIK is effect to high myopic patients with preoperative refraction ranging from-6.00 D to-10.00 D.Refractive regression is occured in some cases after LASIK.Preoperative higher spherical equivalent,lower amount of change in preoperative and postoperative 5 a CCT,less preoperative and postoperative 5 a CCT,less intraoperative laser ablation diameter regression are easy to have refractive regression.Some modification of surgical algorithms and laser nomogram will help to improve predictability and reduce regression.