上皮瓣弃留对机械法准分子激光角膜上皮瓣下磨镶术矫治近视临床疗效的Meta分析

背景近年来，在机械法准分子激光角膜上皮瓣下磨镶术（Epi-LASIK）的手术过程中，角膜上皮瓣保留与否及其对术后角膜上皮的愈合时间、视力恢复等方面的影响逐渐受到人们关注。目的系统评价去除和保留上皮瓣对Epi—LASIK治疗近视的临床疗效。方法采用严密设计的检索策略检索MEDLINE、EMbase、Cochrane图书馆、中国生物医学文献数据库（CBMdisc）、中国期刊全文数据库（CNKI），对有关比较去上皮瓣Epi—LASIK和留上皮瓣Epi，LASIK临床疗效相关研究的文献进行Meta分析。Meta分析的内容包括术后角膜上皮愈合时间、疼痛程度及角膜上皮下雾状混浊（haze）情况。采用RevMan4．2．2进行统计分析，连续性变量以加权均数差（WMD）（95％CI）为疗效分析统计量，计数资料则用优势比（OR）（95％cI）。对检索文献的证据等级按照Jadad量表进行评价。结果共有8篇文献符合本研究的纳入标准，其中251例患者502眼（等效球镜范围0～-10D）纳入本研究。纳入的文献中按Jadad量表评分2篇评为3分，其他6篇评为1～2分，文献质量等级较低。分析显示去上皮瓣组Epi—LASIK术后角膜上皮愈合时间较留上皮瓣组Epi—LASIK短，差异有统计学意义（WMD=-1．32，95％CI：-1．82～-082，P〈0．01）。术后第1天，2组疼痛情况差异无统计学意义（WMD=-0．17，95％CI：－0．55～0．20，P=0．37），而术后第3天和第5天，去上皮瓣组疼痛情况较留上皮瓣组轻，差异均有统计学意义（WMD=-0．99，95％CI：-1．71～-0．28，P〈0．01）、（WMD=-0．94，95％CI：-1．35～-0．54，P〈0．01）。术后1、3、6个月，2组haze发生情况差异均无统计学意义（OR=0．62，95％CI：0．34～1．12，P=0．11）、（OR=0．70，95％CI：0．31～1．55，P=0．38）、（OR=1．14，95％CI：0．58～2．26，P=0．71）。结论去上皮瓣Epi-LASIK与留上皮瓣Epi—LASIK相比，术后角膜上皮愈合时间更短，眼部疼痛程度更轻，而角膜haze情况二者基本相同。

Meta-analysis of clinical effectiveness of on-flap and off-flap epi-LASIK for myopia

Background Recently,whether the epithelial flaps should be removed or preserved during the Epi-LASIK and its affection on clinical results are concerned.Objecfive This system analysis was to evaluate and compare the clinical effectiveness between on-flap Epi-LASIK and off-flap epi-LASIK for myopia. Methods A systematic literature retfieval was conducted in the MEDLINE,EMBase,Coehrane Library,CBM disc,CNKI from 2003 through 2009.The possible differences in reepithelization time,pain sensation,and haze after surgery were compared between on-flap and off-flap Epi-LASIK for myopia.The statistical analysis was performed using a RevMan 4.2 software.The data was extracted,and the methodological quality was evaluated by two reviewers independently with weighted mean difierence(WMD)for the effectiveness analysis and odds ratio(OR)for counting variable.The quality of included literature was scored according to the Jadad Scale. Results A total of 8 studies involving 251 patients(502 eyes)were included in the meta-analysis.Of these eight studies.five studies were randomized clinical trials and the other three studies were retrospective cohort studies.Compared with on-flap Epi-LASIK group,off-flap Epi-LASIK group had a better postoperative outcome in the mean reepithelization time(WMD=1.32,95％CI-1.82to-0.82,P<0.01)and pain scores at 3,5 day(WMD=-O.99,95％CI-1.71 to-0.28,P(0.01)(WMD=-0.94.95％CI-1.35 to-0.54,P<0.01)after surgery.No significant difierenees were found in the eye numbers of haze at 1 month(OR=0.62,95％C1 0.34 to 1.12,P=0.11),3 months(OR=0.70,95％C1 0.31 to 1.55,P=0.38)and 6 months(OR=1.14,95％C1 0.58 to 2.26,P=0.71)between these two types of operation.The pain scores at the first day after surgery was not significantly different between these two groups(WMD=-0.17,95％CI -0.55 to 0.20,P=0.37). Conclusion The effectiveness of off-flap Epi-LASIK is superior to on-flap Epi-LASIK for myopia.Some high-quality randomlizd and control studies are needed for the further clinical evaluation.