非球面人工晶状体度数计算的最优化

Preliminary evaluation of an algorithm to minimize the power error selection of an aspheric intraocular lens by optimizing the estimation of the corneal power and the effective lens position

目的：通过评价非球面人工晶状体（intraocular lens,IOL）屈光度的可预测性,初步开发一种计算屈光度（PIOL）的优化算法。方法：本研究纳入植入非球面IOL（LENTIS L-313,Oculentis Gmb H）65眼,并分为2组：A组8例12眼,PIOL≥23.0D;B组35例53眼,PIOL〈23.0D。术后3mo进行屈光度可预测性评价。参考角膜屈光力估计所致的可变性屈光指数计算出校正的IOL度数（PIOLadj）及屈光结果,根据年龄和解剖学因素得出校正的有效晶状体位置（adjusted effective lens position,ELPadj）。结果：术后A、B两组等效球镜度数分别为-0.75~＋0.75D、-1.38~＋0.75D。A、B两组的PIOLadj和实际晶状体屈光度（PIOLReal）之间无统计学差异（P=0.64、0.82）。BlandAltman分析显示A、B两组PIOLadj和PIOLReal之间的一致性区间分别为＋1.11^-0.96D和＋1.14^-1.18D。Hoffer Q公式和Holladay I公式计算PIOLadj和PIOL之间存在临床和统计学上的显著差异（P〈0.01）。结论：植入非球面IOL白内障手术的屈光可预测性可通过平行轴光学联合线性法则使角膜屈光力及晶状体位置相关误差最小化。

AIM ： To evaluate the refractive predictability achieved with an aspheric intraocular lens（ IOL） and to develop a preliminary optimized algorithmfor the calculation of its power（ PIOL）.METHODS： This study included 65 eyes implanted with the aspheric IOLLENTIS L-313（ Oculentis Gmb H） that were divided into 2 groups： 12 eyes（ 8 patients） with PIOL≥23. 0 D（ group A）,and 53 eyes（ 35 patients） with PIOL23. 0 D（ group B）. The refractive predictability was evaluated at 3mo postoperatively. An adjusted IOL power（ PIOLadj） was calculated considering a variable refractive index for corneal power estimation, the refractive outcome obtained,and an adjusted effective lens position（ ELPadj） according to age and anatomical factors. RESULTS： Postoperative spherical equivalent ranged from-0. 75 to ＋ 0. 75 D and from-1. 38 to ＋ 0. 75 D in groups A and B,respectively. No statistically significant differences were found in groups A（ P = 0. 64） and B（ P =0. 82） between PIOLadjand the IOL power implanted（ PIOLReal）. The Bland and Altman analysis showed ranges of agreement between PIOLadjand PIOLReal of ＋1. 11 to-0. 96 D and ＋1. 14 to-1. 18 D in groups A and B,respectively.Clinically and statistically significant differences were found between PIOLadjand PIOLobtained with Hoffer Q and Holladay I formulas（ P0. 01）.CONCLUSION： The refractive predictability of cataract surgery with implantation of an aspheric IOL can be optimized using paraxial optics combined with linear algorithms to minimize the error associated to the estimation of corneal power and ELP.