Rotationally asymmetric multifocal IOL designs induced asymmetric aberrations. This study will investigate the possibility to improve visual outcomes with the binocular combinations of this rotationally asymmetric multifocal IOL with optimal orientation for each eye.
An artificial eye model with the rotationally asymmetric multifocal IOL was used to produce retinal images. We used a 3D display binocular visual simulator to produce a fixed orientation in one eye of the subject, while different orientations were used to simulate for the fellow eye. Calculations were made for object distances at 0.0 D to -3.0 D in 0.25 D steps using the Landolt C optotypes for a 3 mm pupil with induced spherical aberrations. The monocular and binocular logMAR visual acuities (VA) were examined as a function of object distances in nine subjects. Average binocular VA for all object distances were compared to the monocular VA.
On average, binocular logMar VA improved by 0.048. The maximum improvement was 0.053 in the orthogonal orientation of the monocular orientation eye. Figure 1 shows the binocular VA differences compared to monocular VA for all measured orientations.
Binocular VA with the rotationally asymmetric multifocal IOL design improved about half line. Interestingly, it was found that the VA of orthogonal orientation binocularly was better compared to the other orientations. These findings suggest that the use of orthogonal orientation of the rotationally asymmetric multifocal IOL design can be another binocular approach to optimize visual outcomes.
Fig. 1. Average binocular VA improvements compared to monocular VA at different orientations. The monocular for reference is illustrated in black, whereas the binocular is shown in red.