Effect of decentration and tilt on four novel extended range of vision intraocular lenses regarding far distance

Abstract

Purpose To analyze the effect of decentration and tilt on four novel non diffractive extended range of vision intraocular lenses (IOLs). Methods Acrysof Vivity, LuxSmart Crystal, RayOne EMV and Tecnis Eyhance were compared on the optical bench (power of 22 D each). Modulation transfer functions were obtained and Strehl ratio was calculated in an ISO-2 model. Apertures of 3 mm and 4.5 mm were applied. For qualitative assessment, United States Airforce (USAF) chart images were evaluated. Additional to centered IOLs, tilt of 5 degrees and decentration of 1 mm were applied. Results RayOne EMV was very robust against misalignment but had considerable deterioration of modulation transfer function (MTF) for large aperture with USAF images seriously blurred. Tilt and decentration decreased the performance of Eyhance significantly but had minor impact on the performance of Vivity and LuxSmart. For 4.5 mm aperture, MTF and Strehl ratio decreased markedly for all IOLs compared to 3 mm aperture size. The best MTF and Strehl ratio was obtained for Eyhance IOL well centered for both sizes of aperture. Conclusion Tilt and decentration had a major impact on the performance of Eyhance only, which performed best of all IOLs tested when well centered. With large aperture, performance of all IOLs significantly decreased. Manufacturer's different approaches for these novel IOLs to increase depth of focus by increasing spherical aberration lead to a different performance in respect to contrast function and sensitivity to misalignment. Our results apply to the distance vision. Near vision performance will be evaluated in a separate investigation.