Abstract
Purpose :
Recent innovative trifocal intraocular lenses (IOLs) have been shown to provide patients with great visual acuity at distance, intermediate and near. Defocus curve has been studied as an essential visual performance endpoint to evaluate range of functional vision of multifocal IOLs. The purpose of this study was to simulate the population-based defocus curve and compare against the clinical results.
Methods :
One-hundred virtual eyes have been generated using two-surface reduced eye model. Monte-Carlo approach was adopted by iterating different corneal power and aberration, anterior chamber depth and pupil size. Light-in-the-bucket (LIB) were calculated at varied defocuses from -3.5 D to +1.0 D and transformed to visual acuities and defocus curve. Defocus curves were also measured in patients from two clinical trials (n = 148 and 93 respectively).
Results :
From -3.5 D to +1.0D, simulated mean defocus curve was generally consistent with the two mean defocus curves from the two clinical trials (Figure 1). The largest difference between the simulated visual acuity and clinical visual acuity was 0.059 logMAR and 0073 logMAR while the largest difference between the two clinical studies was 0.038 logMAR. The averaged absolute difference at varied defocus levels was 0.023 and 0.042 logMAR respectively. Between -2.5 D (40 cm equivalent, at near) and 0 D (at distance), simulated and clinical visual acuities were all above 0.1 logMAR, indicating superior visual performance compared to functional visual thresholds (20/32) for daily visual activities.
Conclusions :
The simulated visual acuity and defocus curve using population-based LIB metrics have been generally consistent with clinically reported defocus curve for the trifocal IOL. The population-based simulation of defocus curve can serve as a useful tool for lens design optimization and IOL trial planning.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.