飞秒激光与微型角膜刀制瓣LASIK术后视觉质量比较

Corneal aberrations and visual performance after flap creation of LASIK with a femtosecond laser and a mechanical microkeratome

背景 准分子激光角膜原位磨镶术（LASIK）是目前矫正近视和近视散光的主要手术方式之一,研究表明飞秒激光制瓣LASIK的安全性、精确性及可预测性明显优于微型角膜刀制瓣LASIK,但飞秒激光制瓣LASIK对患者视觉质量的影响仍是关注的焦点. 目的 比较Intralase FS60飞秒激光和Moria M2微型角膜刀制瓣LASIK矫正屈光不正的临床疗效及术后视觉质量. 方法 采用前瞻性非随机临床对照研究方法,纳入2012年3-8月于首都医科大学附属北京同仁医院拟行LASIK治疗近视及近视散光并符合纳入标准的患者共102例204眼.根据自愿的原则将患者分为2个组,各组患者基线特征匹配.飞秒激光制瓣组50例100眼行飞秒激光制瓣的LASIK,微型角膜刀制瓣组52例104眼行微型角膜刀制瓣的LASIK.分别于术前及术后3个月、6个月和1年采用波前像差仪分析6 mm瞳孔下Zernike系数及高阶像差的均方根值,采用Optec 6500视功能测试仪测定暗视及暗视＋眩光状态下1.5、3.0、6.0、12.0和18.0 c/d空间频率的对比敏感度（CS）.结果 飞秒激光制瓣组术后3个月、6个月和1年裸眼视力达到及超过术前最佳矫正视力（BCVA）者分别占95.1％、94.2％和93.9％,微型角膜刀制瓣组分别为94.2％、93.8％和93.2％.术前、术后3个月和术后1年,飞秒激光制瓣组等效球镜度（SE）分别为（-6.37±2.12）、（-0.26±0.45）和（-0.45±0.51）D,微型角膜刀制瓣组分别为（-6.25±2.05）、（-0.44±0.64）和（-0.35±0.59）D,术后3个月和1年2个组间SE比较差异均无统计学意义（u=l.194、1.429,均P＞0.05）.术后3个月、6个月及1年飞秒激光制瓣组总高阶像差（RMSh）及各项高阶像差均明显低于微型角膜刀制瓣组（均P＜0.05）.术后3个月和6个月飞秒激光制瓣组术眼在暗视及暗视＋眩光状态下各空间频率的LogCS值均明显优于微型角膜刀制瓣组,差异均有统计学意义（均P＜0.05）.术后1年,2个组间术眼在暗视状态下1.5 c/d空间频率的LogCS差异无统计学意义（P＞0.05）,而飞秒激光制瓣组术眼在暗视及暗视＋眩光状态下12.0 c/d和18.0 c/d空间频率的LogCS值均明显优于微型角膜刀制瓣组,差异均有统计学意义（均P＜0.05）. 结论 飞秒激光制瓣的LASIK术后产生的高阶像差低于微型角膜刀制瓣的LASIK,视觉质量优于微型角膜刀制瓣的LASIK.

Background Laser in situ keratomileusis （LASIK） for myopia and/or myopic astigmatism still is one of primary surgeries.Femtosecond laser （FS）-LASIK offers several advantages over microkeratomes for flap creation including better safety,reproducibility,and predictability.However,the visual performance after FS-LASIK is of high clinical concern.Objective This study was to compare the visual performance between Intralase FS60 femtosecond laser flap and mechanical microkeratome Moria M2 flap in LASIK.Methods A prospective nonrandomized controlled study was performed.Two hundred and four myopic eyes of 102 patients were enrolled in this study and divided into two groups according to patients’ opinion,with matched demography between the two groups.LASIK with FS60 femtosecond laser flap was performed on 100 eyes of 50 myopia and/or myopic astigmatism in the FS group,and Moria M2 flap LASIK was performed on 104 eyes of 52 patients in the microkeratomes group.Zernike coefficients and the root-mean-square （RMS） of higher order aberrations were measured by Wavescan wavefront aberrometer before and 3,6 and 12 months after surgery,and the contrast sensitivity （CS） in different spatial frequencies under the scotopia and scotopia ＋ glare background was detected using Optec 6500 visual function instrument before and 3,6,12 months after surgery.This study protocol was approved by Ethic Committec of Beijing Tongren Hospital,and written informed consent was obtained from each patient prior to surgery.Results The uncorrected visual acuity （UCVA） levels after surgery reached or was superior to the preoperative best corrected visual acuity （BCVA） in 95.1%,94.2% and 93.9% patients in the FS group and in 94.2%,93.8% and 93.2% patients in the microkeratomes group 3,6,12 months after surgery,respectively.The mean spherical equivalent （SE） was （-6.37 ±2.06）D,（-0.26±0.45）D and （-0.45± 0.51）） in the FS group,（-6.25± 2.43） D,（-0.44± 0.64） D and （-0.35±0.59）D in the microkeratomes group before surgery and 3,12 months after surgery,respectively.There were no significant differences in the SE in various time points between the two groups （u =1.194,1.429;both at P〉 0.05）.The root means square high order （RMSh） and RMS3-6 in the FS group were significantly lower than those in the microkeratomes group 3,6 and 12 months after surgery （all at P〈0.05）.Under the background of scotopia or scotopia＋glare,the LogCS values under different spatial frequencies were significantly higher in the FS group than those in the microkeratomes group 3 and 6 months after surgery （all at P〈0.05）.In 12 months after surgery,no significant difference was found in the LogCS under the 1.5 c/d in the background of scotopia between FS group and microkeratomes group （P〉0.05）,and the LogCS values under the 12.0 c/d and 18.0 c/d in the background of scotopia or scotopia＋glare in the FS group were better than those in the microkeratomes group （all at P〈0.05）.Conclusions Femtosecond laser assistant LASIK has better visual performance and lower higher-order aberrations than microkeratomes assistant LASIK.