Trifocal: Comparison of visual performance of 2 diffractive trifocal intraocular lenses: a randomised controlled trial

Although bilateral monofocal IOL implantation, aiming for emmetropia or low myopia, leads to high levels of patient satisfaction in distance vision, spectacle dependence for reading and other near vision tasks is the usual result. The options commonly used to achieve spectacle independence are multifocal intraocular lenses (IOLs). Multifocal IOLs either use a refractive or diffractive design or a combination of both or segmented asymmetric optics. The principal of the refractive design is based on changing the route of light rays by thickness, curvature and optical density of the lens. The purpose of the study is to compare two commercially available bilaterally implanted diffractive trifocal lenses (one eye = Zeiss AT Lisa tri 839 MP IOL; contralateral eye = Rayner trifocal) with cataract surgery concerning visual function (specifically uncorrected near visual acuity) and spectacle independence.