LASIK治疗近视散光眼术后高阶像差变化的多因素分析

Multiplicity of high order aberration changes after LASIK for myopia and astigmatism

目的探讨LASIK治疗近视散光眼术后高阶像差变化与切削量、治疗光区直径和术后角膜后表面前凸值的相关性。方法随机选取采用飞秒激光制瓣波前像差引导LASIK治疗的近视散光患者69例(138眼),采集患者术前和术后6个月的高阶像差值、角膜后表面前凸值,记录患者的治疗光区直径和切削量,采用多元逐级回归分析探讨手术切削量、治疗光区直径和术后角膜后表面前凸值与术后高阶像差的相关性。结果术中手术切削量为(96.26±25.14)μm,治疗光区直径为(6324.00±297.00)μm,术后6个月角膜后表面前凸值为(47.62±15.00)μm;术后6个月瞳孔直径6 mm区的总体高阶像差和去球差高阶像差均方根值分别为(0.78±0.26)μm、(0.56±0.23)μm,术前为(0.49±0.21)μm、(0.45±0.22)μm,差异均有统计学意义(均为P<0.01)。术后6个月瞳孔直径6 mm区的总体高阶像差和去球差高阶像差均方根值与手术切削量(r=0.62、0.46,均为P<0.01)、术后角膜后表面前凸值(r=0.49、0.45,均为P<0.01)均呈正线性相关,与治疗光区直径(r=-0.56、-0.47,均为P<0.01)均呈负线性相关。结论 LASIK治疗近视散光眼术后高阶像差较术前增大,术后高阶像差增加与手术切削量、术后角膜后表面前凸值呈正线性相关,与治疗光区直径呈负线性相关。

Objective To analyze the correlation of higher order aberration changes with ablation depth, optic zone diameter and posterior corneal surface protru- sion after LASIK for myopia and astigmatism. Methods This prospective study com- prised 138 eyes of 69 patients treated with wavefront-guided LASIK who were available for evaluation at 6 months. The total high order aberrations, posterior corneal surface protrusion, ablation depth and optic zone diameter were measured before and after 6 months postoperatively. Multiple regression analysis was used to assess the factors that affect the change of the higher order aberrations after LASIK. Results The intra-oper- ative ablation depth was （ 96.26 ± 25. 14 ） μm, the optic zone diameter was （ 6324.00 ±297.00）μm, the posterior corneal surface protrusion at postoperative 6 months was （47.62 ±15.00 ） μm. At postoperative 6 months, the total higher order aberrations root mean square （HOARMS）and without spherical aberration HOARMS at 6 mm pupil size were （0.78 ± 0.26 ） μm, （0.56± 0.23 ）μm, which were higher than pre-operation （0.49 ± 0.21 ）μm and（ 0.45 ± 0.22 ）μm, there were significant differences （all P 〈 0.01 ）. Both ablation depth（ r = 0.62,0.46, all P 〈 0.01 ） and posterior corneal surface protrusion（ r =0.49,0.45, all P 〈 0.01 ） showed positive linearity correlations with the total HOARMS and despherical aberration HOARMS. There was a negative linearity correlation between optic zone diameter and total HOARMS, without spherical aberration HOARMS （ r = - 0.55, - 0.47, all P 〈 0.01 ）. Conclusion The postoperative higher order aberration is higher than pre-op- eration after LASIK for myopia and astigmatism, which are positive linearity correlated with ablation depth, posterior corneal surface protrusion, and negative linearity correlated with optic zone diameter.