Halo Measurements in Simulated Multifocal Intraocular Lenses

To quantify the halo size produced by simulated multifocal and extended depth of focus (EDOF) intraocular lenses (IOLs) using a novel psychophysical method, and to compare the results with an established halo assessment tool, computational simulations, and subjective bothersomeness scores.

Ten participants were each presented with ten IOL designs (three trifocals, three EDOFs, three bifocals, and one monofocal) simulated using SimVis Gekko visual simulator (2EyesVision, Spain). Halo size was quantified using both the established Halo V1.0 software and a custom-developed scrolling method designed for rapid halo assessment. Results were compared with computational predictions derived from Fourier optics. Perceived visual disturbance was evaluated using a shortened version of the Assessment of Intra Ocular Lens Implant Symptoms questionnaire.

Trifocals produced larger halos than EDOFs, whereas the monofocal generated the smallest. Measurements obtained with Halo V1.0 and scrolling method were highly correlated (r = 0.99) and showed strong agreement with computational estimations (r > 0.92). Halo size increased with IOL addition power by 5 arcmin/diopter. The scrolling method required less time (29.6 ± 16.2 vs. 283 ± 1.7 seconds) and exhibited lower variability (1 ± 0.8 vs. 5.4 ± 5.8 arcmin) compared to Halo V1.0. Subjective disturbance scores correlated strongly with measured halo (r > 0.98).

SimVis Gekko emulates halo phenomena associated with different IOL designs. The custom scrolling method provides fast, reliable halo assessment with potential for research and clinical application.

Findings support integrating preoperative halo simulation and rapid psychophysical evaluation to enhance personalized IOL selection and patient counseling.