Safety and efficacy of VisuMax®circle patterns for flap creation and enhancement following small incision lenticule extraction

Background:The purpose of this case series is to evaluate the safety and efficacy of VisuMax®Circle patterns in eyes that have undergone small incision lenticule extraction,thus creating a flap to perform an enhancement procedure or residual lenticule extraction.Methods:This prospective,single center,case study series evaluated the use of a VisuMax®Circle pattern to create a corneal flap following small incision lenticule extraction.Patients were treated and followed at TRSC International LASIK Center(Bangkok,Thailand)for 3 months to assess the efficacy and safety of the procedure.Efficacy was determined by the surgeon’s ability to lift the created corneal flap.Results:The study enrolled 28 eyes.Twenty-seven underwent the VisuMax®Circle pattern procedure for refractive enhancement,and one for residual lenticule extraction.In 100%of cases(28 eyes)the lifting of the flap was possible,as planned.In all cases of refractive enhancement(27 eyes)by laser in situ keratomileusis(LASIK),the exposure of the stromal bed was sufficient for the necessary excimer laser ablation.No eyes lost two or more Snellen lines of corrected distance visual acuity(CDVA)and no procedure or flap-related complications or serious adverse events occurred.Conclusions:This initial case series demonstrates that VisuMax®Circle pattern is efficacious and a suitable method to create a corneal flap for enhancement,following small incision lenticule extraction.

飞秒激光制瓣与机械刀制瓣LASIK术后角膜皱褶和移位发生的比较

目的对机械刀制瓣与飞秒激光制瓣LASIK引起的术后早期角膜瓣皱褶和移位发生的比较。方法回顾性分析2016年1月至2017年1月收治的5 792例LASIK的临床资料。患者随机分为两组:A组飞秒激光制瓣组和B组机械刀制瓣组。选取术后早期无明显外伤史而出现Ⅱ级以上角膜瓣皱褶和移位患者作为研究对象,比较两组之间发生率以及可能的原因。结果A组共3 358例,其中出现角膜瓣皱褶和移位15例,发生率0.45%;B组共2 434例,其中出现角膜瓣皱褶和移位22例,发生率0.90%,两组差异有统计学意义(χ^2=4.647,P=0.031)。A组移位者术前等效球镜度为(-7.71±1.38)D,B组移位者为(-5.56±1.90)D,A组移位者近视度高于B组移位者(t=-3.99,P=0.0003)。A组移位者角膜瓣厚度为(83.80±4.74)μm,B组移位者角膜瓣厚度为(92.32±6.39)μm。两组移位者角膜瓣厚度分别与各组相应正常者角膜瓣厚度相比差异无统计学意义(t=0.34,P=0.73;t=-0.38,P=0.71)。结论角膜瓣皱褶和移位发生率与术前患者的屈光度及术式有关,与角膜瓣厚度无相关性,飞秒激光制瓣LASIK更具有良好的瓣稳定性。