偏心和旋转对非球面Toric人工晶状体成像质量影响的实验研究  

The Optical Performance Parameters for Rotation and Decentration of the Aspherical Biconvex Toric Intraocular Lens

作　　者：张斌[1] 刘丹岩[1] 柴茜楠[1] 魏玉华[1] 杜颖华[1] 段洁[2] 邢国献 

机构地区：[1]河北医科大学第二医院眼科,石家庄050000 [2]河北医科大学第二医院全科医学科,石家庄050000 [3]阜平县中医院内科,保定073200

出　　处：《中华眼视光学与视觉科学杂志》2018年第1期19-25,共7页Chinese Journal Of Optometry Ophthalmology And Visual Science

摘　　要：目的：通过对Toric人工晶状体（IOL）的球差进行自动优化，理论设计不同球差的Toric IOL，并且对其旋转、偏心的耐受性及成像规律进行研究。方法：实验研究。在模型眼中对Toric IOL球差进行优化，分别优化球面结构，IOL前、后表面曲率半径和厚度及Toric IOL的前表面非球面系数，目标设计获得-0.26、-0.1 和0 μm球差的Toric IOL。在计算机光学模拟系统中，球面和非球面Toric IOL沿其X轴分别偏心0.25、0.50、0.75 mm，在3 mm和5 mm瞳孔直径下，评价其对调制传递函数（MTF）的影响；使其旋转3°、5°、10°，在4 mm瞳孔直径下评价其对MTF的影响。结果：在居中时随着瞳孔直径的增大，非球面Toric IOL成像质量下降低于球面Toric IOL；但在3 mm瞳孔偏心0.50 mm时，-0.26 μm的Toric IOL的成像质量下降并且低于0 μm和-0.1 μm的Toric IOL；5 mm瞳孔直径时偏心0.75 mm，-0.26 μm球差Toric IOL的MTF与球面IOL接近，而0 μm和-0.1 μm球差的Toric IOL的MTF略优于球面Toric IOL。旋转3°和5°时，非球面Toric IOL MTF仍高于球面IOL；旋转10°时，非球面Toric IOL高空间频率的MTF已经接近或低于球面IOL。结论：-0.26 μm球差的Toric IOL居中时有良好的成像质量，但偏心耐受性较差。对Toric IOL球差的适量的优化，可以提高模型眼的成像质量，同时保持对偏心和旋转误差的耐受性，使其在综合条件下获得更好的光学质量。Objective： To optimize the spherical aberrations of toric intraocular lens （IOL）： to design toric IOLs with different spherical aberrations, and to study the rotation, the tolerance to decentration, and imaging rules. Methods： In this experimental study, the spherical aberrations of toric IOLs were optimized in the Hwey-Lan Liou model eye. The spherical structure, the curvature radius, and the thickness of the anterior and posterior surfaces of the toric IOLs, and the aspheric coefficients of the anterior surface of toric IOLs were optimized respectively. The targets was optimized to produce IOLs with -0.26 μm, -0.1 μm and 0 μm spherical aberrations. In the computer optical simulation system, the effect on the modulation transfer function （MTF） was evaluated when spherical and aspherical IOLs were decentrated in the horizontaldirection with 0.25 mm, 0.50 mm and 0.75 mm at 3- and 5-mm pupil diameters. The effect on MTF was also evaluated when the two types of IOLs were rotated by 3°, 5° and 10° at 4-mm pupil diameter. Results：At the center, the aspherical toric IOL displayed a better image performance with the increased pupil diameter. When the decentration was 0.5 mm at 3-mm pupil diameters, the imaging quality of the -0.26 μm toric IOL decreased and was worse than that of 0 or -0.1 μm IOL. At 5-mm pupil diameter, when the decentration was 0.75 mm, the MTF of -0.26 μm toric IOL was close to that of the spherical toric IOL, while the MTF of toric IOL with 0 μm and -0.1 μm spherical aberration was slightly better than that of the spherical toric IOL. The MTF of aspherical toric IOLs was better than that of the spherical toric IOL with 3° to 5° rotation, but the curve was equal or even worse than that of the spherical toric IOL with 10° rotation in high spatial frequency. Conclusions： Toric IOLs with a spherical aberration of -0.26 μm have good imaging quality at the center but lower tolerance to decentration. The proper optimization of the spherical aberration of toric IOLs can im

关 键 词：白内障 人工晶状体 散光 角膜 偏心 旋转 调制传递函数 模型 

分 类 号：R779.6[医药卫生—眼科]