Modeling The Effect Of Pupil Size On Non-Diffractive Wavefront-Shaping Extended Depth Of Focus Intraocular Lens

To assess the in-vitro Performance of the Non-Diffractive Wavefront-Shaping Extended Depth of Focus Intraocular Lens (EDOF IOL) (Alcon Acrysof IQ Vivity) across various pupil sizes.

Rothschild Foundation Hospital, Paris, France.

In vitro wavefront acquisition of the Acrysof IQ Vivity, with a 20-diopter power, was conducted using the NIMO TEMPO (Lambda-X, Nivelles), an intraocular lens wavefront sensor. Through-focus average Modulation Transfer Function (MTF) (between 0 and 50 lp/mm) was calculated for synthetic numerical modified ISO-2 eye models with 8 different apertures ranging from 2 to 5.5mm, at intervals of 0.5mm, and various corneal spherical aberrations (SA), ranging from -0.14 to 0.56μm at a 5.15mm diameter in the IOL plane, with increments of 0.14μm. This analysis was conducted on a total of 42 distinct eye models.

Analysis of the through-focus MTF curve of the various eye models reveals that the Vivity presents a displaced MTF peak at higher power values at 2 and 2.5mm pupils compared to other pupil sizes in model eyes without residual spherical aberrations. This difference was more pronounced with negative residual spherical aberrations, whereas positive residual spherical aberrations reduce this gap.

The special plateau design of 2.2mm of the Acrysof IQ Vivity lens enables an EDOF effect but may lead to an adverse consequence of increased optical power in pupils equal to or smaller than 2.5mm. Caution is warranted when considering the implantation of this lens in patients with small photopic pupils and significant pupil size amplitude with large mesopic pupils, as IOLs that provide emmetropia under normal or mesopic conditions could result in myopia in high luminosity conditions. This refractive instability with illumination is more pronounced in normal corneas with low spherical aberrations or negative spherical corneal aberrations, as seen in post-hyperopic refractive surgeries.