不同波前像差引导的准分子激光原位角膜磨镶术术后暗环境视力的对比研究

Comparative study of postoperative scotopia after LASIK guided by different wavefront aberrations

目的比较不同波前像差引导的准分子激光原位角膜磨镶术(LASIK)对术后暗环境视力的影响。方法在我院拟行LASIK的近视患者中,选取瞳孔直径6 mm时,全眼高阶像差均方根(RMS)值>0.25μm的患者201例(201眼),随机分为4组,每组均接受不同波前像差引导的LASIK治疗,其中A组接受除彗差外的波前像差引导LASIK;B组接受除三叶草外的波前像差引导LASIK;C组接受除球差外的波前像差引导LASIK;D组接受所有像差矫正的波前像差引导LASIK。比较术前及术后1周、1个月、3个月的裸眼视力,6 mm瞳孔直径下全眼总高阶像差RMS值,球差、彗差、三叶草像差Zernike多项式值,及暗环境下100%、25%、10%、5%不同对比度下的视力。结果术前及术后不同时间点各组裸眼视力相比差异均无统计学意义(均为P>0.05)。术后各组各时间点全眼总高阶像差和球差均较术前有显著性增加(均为P<0.05)。C组术后球差与A组、B组、D组相比差异均有统计学意义(1周对P值分别为0.012、0.029、0.009;1个月时P值分别为0.039、0.046、0.017;3个月时P值分别为0.041、0.027、0.002)。暗环境10%对比度下C组、D组间在术后1周、1个月时视力差异均有统计学意义(P=0.029、0.045);5%对比度下术后1周时A组与D组、C组与D组间及术后1个月时C组与D组间视力差异均有统计学意义(P=0.034、0.020、0.042)。结论彗差比三叶草像差更影响视觉,球差对视觉质量影响最大。现有的临床水平下矫正三叶草像差意义不大,矫正球差更有意义。

Objective To compare the influences of laser- assisted In-situ Kera- tomi（LASIK） guided by different wavefront aberrations on postoperative scotopia. Methods According to the criteria that total higher order aberration （tHOA） root- mean-square（RMS） was higher than 0.25 μm when pupil diameter was 6 ram,201 pa- tients（201 eyes） were selected from myopic patients who had been preparing to have LASIK in our hospital. The patients were then randomly divided into 4 groups,and each group received LASIK guided by different wavefront aberration. Group A received LASIK guided by all wavefront aberrations but coma; group B received LASIK guided by all wavefront aberrations but trefoil aberration;group C received LASIK guided by all wave- front aberrations but spherical aberration （SA） ; group D received LASIK guided by all wavefront aberrations. A series of factors including uncorrected visual acuity（ UCVA）, RMS of tHOA when pupil diameter was 6 ram, answer of Zemike polynomials evalua- tions of SA, coma and trefoil aberration, and scotopia under different contrast ratio （100% , 25% , 10% ,5% ） were measured at 4 points-in-time（preoperative point-in-time,1 week, 1 month and 3 months after the operation） and compared. Results No significant difference was found between UCVA of each group at any points-in-time （ All P 〉 0.05 ）. tHOA and SA of each group at all postoperative points-in-time were significantly higher than preoperative ones （ All P 〈 0.05 ）. SA of group C was significantly different from that of the other 3 groups at all 3 postoperative points-in-time （ 1 week, P = 0. 012,0. 029,0.009 ; 1 month, P = 0. 039,0. 045,0. 017 ; 3 months,P =0.041,0.027,0.002） Significant differences were found between scotopia of group C and group D at the 2nd and 3rd points-in-time when the contrast ratio was 10% （P = 0. 029,0. 045 ）. When the contrast ratio was 5% , scotopia of group A and group D at the 2nd point-in-time were significantly different from each other（P = 0.034） ;Significant differences were found between scotopia of group C and group D at the 2nd and 3rd points-in-time（P = 0.020,0.042）. Conclusion Coma has a greater influence on vision than trefoil aberration. The influence of SA on visual quality is the greatest of the three. Given present clinical level, correcting SA is of much more significance than correcting trefoil aberration.