飞秒激光Ziemer FEMTO LDV“Classic”和“Crystal Line”制作LASIK角膜瓣的评估

Evaluation of corneal flaps made by femtosecond laser Ziemer FEMTO LDV “Classic” and “Crystal Line LASIK”

目的比较Ziemer"Classic"和Ziemer"Crystal Line"飞秒激光制作角膜瓣的规则性、准确性及预测性。方法对近视患者60例120眼行F-LASIK手术,其中Ziemer"Classic"组(A组)及Ziemer"Crystal Line"组(B组)制作角膜瓣的患者各30例60眼。术后1周,应用RTVue OCT分别测量两组患者每个角膜瓣上36个测量点的角膜瓣厚度值进行对比分析。两组飞秒激光角膜瓣预计值均为110μm。结果术后1周,B组平均角膜厚度(103.09±2.38)μm明显低于A组(106.93±4.86)μm(P<0.01)。B组角膜瓣从中央到周边的规整性明显好于A组。A组角膜瓣厚度值与预计厚度110μm的最大差值为7μm,B组最大差值为8μm。A组60只眼总共2 160个测量点中,有0.14%的点角膜瓣厚度与预计值110μm的差值大于20μm,而B组为0.02%。结论与Ziemer"Classic"飞秒激光比较,Ziemer"Crystal Line"飞秒激光制作的角膜瓣更薄,其角膜瓣的均一性和预测性相对更好一些。

Objective To compare the effectiveness of LASIK flaps created with the Ziemer FEMTO LDV “Classic”femtosecond laser and Ziemer FEMTO LDV Crystal Line femtosecond laser.Methods Fourier-domain optical coher-ence tomography （ RTVue OCT） was used to measure the shapes of 120 LASIK flaps one week postoperatively in the patients created with the Ziemer“Classic” femtosecond laser （ group A, 60 flaps） or the Ziemer Crystal Line femtosec-ond laser （ group B, 60 flaps） .The flap thickness was determined by 36 specified points on each flap.The regularity, uniform and accuracy of Ziemer “Classic” FS and Ziemer Crystal FS were compared.Nominal flap thickness was 110μm for two FS systems.Results The mean flap thickness of group B was thinner than that of group A （103.09 ± 2.38 v.s.106.93 ±4.86μm;P〈0.01, t-test for independent-samples）.The flaps in group B were more regular than those in group A when measured from the center to the periphery.The maximum deviation from the pre-determined 110μm was 7μm in group A and 8μm in group B.Among the total 2160 measured points in 60 eyes, differences greater than 20μm were noted in 0.13%of group A and 0.02%of group B.Conclusion The flaps created with Ziemer Crystal Line femtosecond laser are more consistent and thinner than those created by Ziemer“Classic” femtosecond laser.