Franchini Alessandro
Optical Physiopathological Department, University of Florence, Florence, Italy.
J Cataract Refract Surg. 2007 Mar;33(3):497-509. doi: 10.1016/j.jcrs.2006.11.018.
To evaluate the performance of 4 aspheric intraocular lenses (IOLs) in scotopic lighting conditions to determine the IOL with the best image quality at different spherical and chromatic aberrations and depths of focus.
Eye Institute, Optic Physiopathological Department, University of Florence, Florence, Italy.
Four IOLs were tested. In the Tecnis (Advanced Medical Optics, Inc.), IQ (Alcon Surgical), and KS-3Ai (Staar Surgical) IOLs, the aspheric profile is on the anterior surface of the optic. In the SofPort IOL (Bausch & Lomb), it is on the anterior and posterior surfaces and is preloaded in the injector. Spot diagrams were used to capture light dispersion, monochromatic point-spread function (PSF) to evaluate the light distribution on the fovea of the eye model, and monochromatic modulation transfer function (MTF) to evaluate image contrast. Depth of focus was evaluated at best focus and -0.08 mm and +0.08 mm from best focus.
The spot diagrams for the Tecnis IOL were well-focused within a diameter of 10 microm. For the other aspheric IOLs, the pattern was broader, indicating greater dispersion and larger chromatic aberrations. The monochromatic PSF and Strehl ratios favored the Tecnis lens, demonstrating that light energy is focused on the area of the eye model that represents the fovea. The monochromatic MTF showed higher contrast levels for the Tecnis lens than the other IOLs at yellow and blue wavelengths, but the KS-3Ai had higher contrast at the red frequency. The depth of focus testing showed overlapping of the yellow and blue frequencies and partial overlapping of the yellow, blue, and red for the Tecnis lens, indicating good depth of focus. The IQ IOL had higher luminance but less overlap. The SofPort and KS-3Ai IOLs had lower luminance thresholds.
It is possible to find the compromise in which residuals of spherochromatic aberration enhance the depth of focus by decreasing the image sharpness or the amount of light on the fovea. The Tecnis IOL provided the best compromise between spherical and chromatic aberrations and depth of focus.
评估4种非球面人工晶状体（IOL）在暗视照明条件下的性能，以确定在不同球差、色差和焦深情况下具有最佳图像质量的IOL。
意大利佛罗伦萨大学佛罗伦萨眼科学院视光生理病理科。
对4种IOL进行测试。在Tecnis（Advanced Medical Optics公司）、IQ（爱尔康外科）和KS - 3Ai（STAAR外科）IOL中，非球面轮廓位于光学部的前表面。在SofPort IOL（博士伦）中，非球面轮廓位于前表面和后表面，并预装在注射器中。使用点列图来捕捉光散射，单色点扩散函数（PSF）来评估眼模型中央凹上的光分布，单色调制传递函数（MTF）来评估图像对比度。在最佳焦点以及最佳焦点±0.08 mm处评估焦深。
Tecnis IOL的点列图在直径10微米范围内聚焦良好。对于其他非球面IOL，光斑更宽，表明散射更大且色差更大。单色PSF和斯特列尔比有利于Tecnis晶状体，表明光能聚焦在眼模型中代表中央凹的区域。单色MTF显示，在黄色和蓝色波长下，Tecnis晶状体的对比度水平高于其他IOL，但KS - 3Ai在红色频率下具有更高的对比度。焦深测试显示，Tecnis晶状体的黄色和蓝色频率重叠，黄色、蓝色和红色部分重叠，表明焦深良好。IQ IOL亮度更高但重叠较少。SofPort和KS - 3Ai IOL的亮度阈值较低。
有可能找到一种折衷方案，即球色差残余通过降低图像清晰度或中央凹上的光量来增强焦深。Tecnis IOL在球差、色差和焦深之间提供了最佳折衷方案。
