PURPOSE: This work aims to evaluate the halo patterns produced in far vision by two extended range of vision (ERV) intraocular lenses (IOLs), focusing on their spatial extent and intensity. The objective quantification of halos aids in the understanding of dysphotopsia, a condition that can significantly impact visual performance.

METHODS: Halo formation in distance vision with the ERV IOLs B+L enVista Beyond and Alcon Vivity was evaluated objectively using an optical bench. Both lenses had a nominal power of 20 D. The Beyond model is a free spherical aberration (SA) IOL, whereas the Vivity incorporates SA = -0.20 microns for a 5.15-mm pupil at the IOL plane (IOL-pupil). The experimental setup employed an artificial eye model compliant with ANSI Z80.35-2018, featuring an artificial cornea with SA = +0.27 µm (5.15-mm IOL-pupil). Illumination of a 3.44-arcmin pinhole target was provided by a warm-white high-intensity LED combined with a V(λ) photopic filter to simulate the human visual sensitivity.

RESULTS: Images at the far focus plane for both IOLs using IOL-pupils of 3.0 and 4.5 mm are shown in Figure 1. The larger, 4.5-mm pupil corresponds to mesopic distance-vision conditions, such as nighttime driving. All images were processed applying a gamma correction of 0.4 to enhance the visibility of the surrounding halo structures. For the 4.5-mm pupil, the two lenses exhibited halos of comparable extent and intensity, whereas at 3.0 mm the Beyond IOL generated a slightly smaller and more compact halo pattern (Figure 2).

CONCLUSIONS: Halo formation with two ERV IOLs was assessed using an ANSI Z80.35-2018 compliant model eye on an optical bench under white-light conditions. Both lenses exhibited halo patterns of similar size and intensity, with minimal dependence on pupil diameter at 3.0 and 4.5 mm. A modest reduction of the halo was noted for the enVista Beyond lens at 3.0 mm. These findings provide preclinical evidence that may help guide clinicians in selecting the most appropriate IOL for patients undergoing cataract surgery.