高度近视LASIK治疗中角膜瓣厚度的探讨

The corneal flap thickness in laser in situ keratomileusis for high myopia

目的:探讨高度近视LASIK治疗中角膜瓣厚度问题。方法:142例(283眼)屈光度-9.00～-12.00 D的近视患者用日本NIDEK MK-2000全自动微型板层角膜切割刀切开角膜瓣,厚度71～184μm,激光切削方式一致。将角膜瓣厚度≤110μm分为Ⅰ组,72例(144眼);角膜瓣厚度>110μm分为Ⅱ组,70例(139眼)。对术前、术后屈光度、视力以 及剩余角膜基质床厚度进行比较。结果:术前平均角膜厚度:Ⅰ组为(531.76±30.28)μm(469～575μm),Ⅱ组为(550.66±24.45)μm(506～584μm),两者有明显差异(P<0.05)。术后剩余角膜基质床厚度:Ⅰ组为(333.01±3.30)μm(273～452μm),Ⅱ组为(309.71±31.41)μm(254～368μm),两者有明显差异(P<0.05)。术前屈光度两组分别为(-10.61±1.01)D及(-10.13±0.73)D,两组间无明显差异(P>0.05),术后7 d时分别为(+1.05±1.38)D及(+1.32±1.70)D,两组间也无明显差异(P>0.05),而术后3m Ⅰ组为(-0.13±0.94)D,Ⅱ组为(-1.06±0.96)D,两组有明显的差异(P<0.01)。术前、术后不论UCVA还是BCVA,两组无明显差异(P>0.05)。结论:治疗高度近视时70～110μm的角膜瓣的制作是合理的,并不影响术后视力,对防止术后屈光回退是有效的,对一个有经验的医生来说是可以很好完成的。

Objective: To evaluate the comeal flap thickness in laser in situ keratomileusis for high myopia. Methods: Two hundred eighty-three eyes of 142 patients with high myopia( - 9. 00--12. 00)D who received LASIK. They were divided into 2 groups accoiding to their corneal flap thickness. Group I was≤110μm(144 eyes), group Ⅱ was > 110μm( 139 eyes). The pre-LASIK and post-LASIK refractive diopter, visual acuity, residual stromal thickness were compared. Results: The mean pre-LASIK corneal thickness: there were obvious difference(P < 0.05) between group I(531. 76±30.28)μm and group Ⅱ (550.66±24.45)μm, the mean post-LASIK residual stromal thickness: there were obvious difference( P < 0.05) between group I(333.01±39.30)μm and and group Ⅱ(309.71 ±31.41 )μm. The mean refractive diopter on pre-LASIK, post-LASIK 7th day, 3 rd month was (- 10.61±1.01)D,( + 1.05±1.38)D, and ( -0.13± 0.94)D in group I,while that in group Ⅱ for same time was (-10.13±0.73)D, ( + 1.32±1.70)D,and ( - 1.06±0.96)D respectively. Statisticlly obvious difference between 2 groups was on post-LASIK 3rd month(P < 0.01), obvious difference were not found for other time(P > 0.05) . There were no statistical difference of visual acuity (including UCVA and BCVA) between 2 groups on pre-LASIK,post-LASIK 3rd month(P > 0.05). Conclusion: It is reasonable that the corneal flap thickness was 70-110μm in LASIK for high myopia. The thinner comeal flap didn' t affect post-LASK visual acuity and make residual stromal thick to prevent refractive regression.