散瞳前后瞳孔中心偏移对波前引导准分子激光原位角膜磨镶术手术的影响

The influence of pupil center shift on wavefront-guided laser in situ keratomileusis

目的探讨根据散瞳后的瞳孔中心调整切削区对波前引导的个体化准分子激光原位角膜磨镶术(LASIK)疗效的影响。方法瞳孔直径为6mm时高阶像差均方根(RMS)>035μm的近视患者32例(63只眼),随机分为A、B两组,接受Zyoptix个体化LASIK手术。A组以瞳孔中心为切削区中心,B组则根据测得散瞳后瞳孔中心的偏移量对切削区中心作相应调整。结果散瞳后瞳孔中心平均发生(0173±0114)mm的偏移,最大达051mm。术后3个月两组患者视力、屈光度数差异无统计学意义(P>005),波前像差检查显示手术前后彗差的差值分别为(0025±0137)和(0097±0118)μm(t=2131,P=0037),而球差差异无统计学意义(P>005)。B组彗差的矫正效果优于A组。结论散瞳后瞳孔中心普遍发生偏移,根据其偏移量在术中对切削区中心作相应调整可提高彗差的矫正效果。(中华眼科杂志,2005,412426)

Objective To evaluate the pupil center shift quantitatively after pupil dilation and to investigate its influence on the outcome of wavefront guided LASIK. Methods Sixty-three eyes in 32 myopic patients with order RMS higher than 0.35 or were divided into groups A and B, and the Zyoptix LASIK was applied to the patients of both groups In group A, pupil center was used as the center of ablation, while in group B the ablation center was adjusted based on the pupil center shift. Results A (0.173±0.114)mm mean pupil center shift was observed in this study, with the maximum 0.51 mm. At 3 months after the operation, there was no significant difference in visual acuity and refraction power between the two groups. However, the reduction of coma was (0.025±0.137) μm and (0.097±0.118) μm in groups A and B respectively (t=2.131, P=0.037). The change in spherical aberration was significantly different between the two groups. Conclusions Pupil center shift after dilation is common. Adjustment of ablation center based on the shift may improve the correction of coma.