The following IOLs were analyzed: a monofocal AcrySof, a bifocal AcrySof IQ Restor SN6AD1, a trifocal AcrySof IQ PanOptix TFNT00 (all three lenses from Alcon, Fort Worth, USA), and an extended-depth-of-focus (EDOF) TECNIS® Symfony ZXR00 (Abbott Medical Optics, Santa Ana, USA). Table 1 summarizes the key characteristics of the studied lenses.
The aspheric AcrySof IQ Restor SN6AD1 has a refractive base dedicated to refracting incident light rays to far focus and a diffractive grating that creates a secondary (near) focus. The diffractive design features apodization that further amplifies distance vision with increasing pupil size by decreasing the diffractive step-height towards the periphery.
The AcrySof IQ PanOptix TFNT00 features a central refractive-diffractive area of 4.5 mm in diameter that is encircled by a refractive ring in the periphery. According to the manufacturer, the diffractive zone incorporates a quadrifocal optic with three unsequential diffraction orders distributing light rays to far, intermediate, and near foci, while the fourth-order further reinforces far vision.
The TECNIS® Symfony ZXR00 is based on a proprietary echelette design with a diffractive-refractive surface that is intended not only to generate the EDOF but also to counteract the chromatic aberration and thereby improve contrast sensitivity.
All studied lenses share an equal base power of +21.0 D.
The aspheric AcrySof IQ Restor SN6AD1 has a refractive base dedicated to refracting incident light rays to far focus and a diffractive grating that creates a secondary (near) focus. The diffractive design features apodization that further amplifies distance vision with increasing pupil size by decreasing the diffractive step-height towards the periphery.
The AcrySof IQ PanOptix TFNT00 features a central refractive-diffractive area of 4.5 mm in diameter that is encircled by a refractive ring in the periphery. According to the manufacturer, the diffractive zone incorporates a quadrifocal optic with three unsequential diffraction orders distributing light rays to far, intermediate, and near foci, while the fourth-order further reinforces far vision.
The TECNIS® Symfony ZXR00 is based on a proprietary echelette design with a diffractive-refractive surface that is intended not only to generate the EDOF but also to counteract the chromatic aberration and thereby improve contrast sensitivity.
All studied lenses share an equal base power of +21.0 D.