Epi-LASIK对近视眼高阶像差的影响

Influence of Epi-LASIK on high-order aberrations of myopic eyes

目的:探讨微型角膜刀准分子激光上皮瓣下角膜磨镶术(Epi-LASIK)对近视眼波前像差,尤其是高阶像差的影响。方法:应用Custom VueTM波前像差仪采集31例(62眼)行Epi-LASIK手术的近视患者的术前及术后1,6mo的波前像差,对所得的数据进行统计学分析。结果:Epi-LASIK术前的波前像差的分布以低阶像差占优势,为(90.12±1.02)%,高阶像差占(9.88±2.03)%。术后1mo高阶像差显著增加,整体高阶像差及各级高阶像差与术前比差异有显著性(P<0.01),高阶像差占(59.24±2.14)%,低阶像差占(40.76±3.06)%,高阶像差整体平均增加2.52倍,以二次彗差增加最多,达3.03倍,以二次球差增加其次,达2.84倍。术后6mo高阶像差占(51.74±3.08)%,低阶像差占(48.26±4.21)%。与术前相比,整体高阶像差差异仍有显著性(P<0.01),二次彗差和二次球差比术前仍有显著增加(P<0.01),但优势高阶像差彗差和球差逐渐恢复到术前水平,差异无显著性(P>0.05)。与术后1mo相比,高阶像差均有所减小,差异有显著性(P<0.01)。术前近视度数与术后各时期的整体高阶像差呈正相关,差异有显著性(P<0.01)。结论:常规Epi-LASIK术后高阶像差比术前明显增大,以二次彗差和二次球差为最显著,随着时间的推移有所减小,但不能恢复术前水平。术前近视度数越高,术后高阶像差越大。

AIM： To observe and evaluate the influence of epipolis laser in situ keratomileusis （Epi-LASIK） on high-order aberrations in myopic eyes. METHODS： Sixty-two myopic eyes （31cases） were evaluated by the Custom VueTM wave analyzer at pre- Epi-LASIK, 1 month, and 6 months after Epi-LASIK. The root mean square （RMS） values of aberrations were analyzed by SPSS10.0 statistics software. RESULTS： Before Epi-LASIK, the constituent ratio of low order aberrations was （90. 12 ± 1. 02）%, and high-order aberrations accounted for（9.88 ± 2.03） %. One month after surgery, high-order aberrations had increased significantly （P〈0.01）. The constituent ratios of low order aberrations and high-order aberrations were （40. 76 ± 3. 06）% and （59. 24 ± 2.14）% respectively. The total number of highorder aberrations increased 2. 52 times over that preoperatively, especially second coma increased 3. 03 times, spherical aberration increased 2. 84 times. Six months after Epi-LASIK, the constituent ratios of low order aberrations and high-order aberrations were（48.26 ± 4.21 ）% and（51.74 ± 3.08）%. The total number of highorder aberrations, second coma and spherical aberration were larger than that preoperatively（ P〈 0.01 ）. Advantageous high-order aberrations had decreased with time. There was a significant positive correlation between severity of myopia and the total number of high-order aberrations after surgery（ P 〈 0.01 ）. CONCLUSION： Conventional Epi-LASIK increases highorder aberrations, especially second coma and spherical aberration, high-order aberrations after surgery tend to decrease with time, but can not return to preoperative values. The higher the myopia was, the greater the number of high-order aberrations were after surgery.