Defocus Testing of Extended Range of Vision IOL: Simulations and Clinical Outcomes
To explore the differences between defocus curves for extended range of vision IOLs obtained through four different measurement methods: lab-based through-focus image quality, computer-simulated defocus curves, measurements using an adaptive optics vision simulator (AOVS), and as clinically obtained.
The through-focus performance of TECNIS Symfony Extended Range of Vision IOL, model ZXR00, was evaluated in laboratory and clinical settings. Measurements included through-focus image quality testing on an optical bench, computer-simulated defocus curves, defocus curves obtained for subjects using an AOVS. The results were compared to clinically obtained defocus curves.
Visual acuity at distance was better than 0.0 logMAR for the three methods that determined visual acuity (simulations, AOVS, and clinical results). Up to and including ‑2.0 diopters of defocus, the simulations and AOVS predicted the clinically‑obtained defocus curve within 0.1 logMAR. For higher values of defocus, the simulations overestimated the clinically obtained defocus curve, and the AOVS slightly underestimated the clinically obtained defocus curve. Correlation of the image quality on the optical bench and the clinically‑obtained defocus curves varied, depending on the spatial frequency evaluated.
Simulation of defocus curves and measurements using an AOVS correspond well with clinically‑obtained defocus curves of extended range of vision IOLs for defocus values up to and including -2.0 diopters. Prediction of defocus curves using through-focus image quality measured on an optical bench depends on the spatial frequency evaluated.