两种不同制瓣方式对LASIK术角膜瓣厚度的影响

Comparison of LASIK flap thickness created with Ziemer LDV femtosecond laser and Moria M2 mechanical microkeratome

目的:比较ZiemerLDV飞秒激光与MoriaM2机械板层刀不同制瓣方式对LASIK术角膜瓣厚度的影响。方法:选取近视患者100例200眼(近视度数-2.00～-12.00D,散光度数0.00～-3.50D),分别应用ZiemerLDV飞秒激光(设定角膜瓣切削厚度110μm)与MoriaM2(110刀头)微型角膜刀制作角膜瓣,各50例100眼。术后1wk,应用眼前节RTVueFD-OCT测量,每个角膜上0°,45°,90°,135°四条子午线所在截面上中心点、距离中心1,2,3mm特定7个点(共计28个点)的角膜瓣厚度测量,并作分析比较。结果:角膜瓣中央点厚度:ZiemerLDV飞秒激光组108.69±11.75μm,MoriaM2微型角膜刀组130.75±13.36μm,所有观测点(共28点)两组间有明显统计学差异(P<0.01)。角膜中心点厚度与预计值差值比较:ZiemerLDV飞秒激光组9.70±6.84μm,MoriaM2微型角膜刀组21.63±11.79μm。ZiemerLDV飞秒激光组预计值差值明显低于MoriaM2微型角膜刀组(t=17.493,P<0.01)。ZiemerLDV飞秒激光组与MoriaM2微型角膜刀组同一截面中各点角膜瓣厚度值差异有统计学差异(P<0.01)。结论:角膜瓣制作方式相比,在角膜瓣的精确性、可预测性等方面ZiemerLDV飞秒激光优于MoriaM2微型角膜刀。ZiemerLDV组与MoriaM2机械板层刀组都未表现角膜瓣厚度的均匀性。

AIM： To compare corneal flap thickness created with Ziemer LDV femtosecond laser and Moria M2 mechanical microkeratome. METHODS： A retrospective analysis of 100 cases （200 eyes） were performed with myopia and astigmatism （sphere -2.00- -12.00 diopters[D];cylinder 0.00- -3.50 diopters[D]）. Fifty cases （100 eyes） were treated with Ziemer LDV femtosecond laser （Intended flap thickness was 110μm） and fifty cases （100 eyes） were treated with Moria M2 mechanical microkeratome using the 110μm head. Corneal flaps parameters were measured at center and 1mm,2mm,3mm from center located in meridian 0°,45°,90°,135°section, each section including seven points evaluated by RTVue FD-OCT one week after procedure. All measurement points were analyzed. RESULTS： The mean flap thickness at center was 108.69±11.75μm in Ziemer group and 130.75±13.36μm in Moria M2 group. There was a statistical difference in relative points between the two groups （t=24.791,P0.01）. The mean value of each section by subtraction a target flap thickness of 110μm was 9.70±6.84μm in Ziemer group and 21.63±11.79μm in Moria M2 group at center. Ziemer group was significantly less than Moria M2 group （t=17.493,P0.01）. Flap thickness of seven points in the same section were significantly different in both Ziemer group and Moria M2 group（P0.01）. CONCLUSION：Flap creation with Ziemer LDV femtosecond laser was superior to Moria M2 mechanical microkeratome in precision and predictability. The flap thickness of different point in the same section was not equal in two groups.