In Vitro Performance Comparison Between Aspherical Intraocular Lens With Positive Spherical Aberrations Add And Standard Positive Spherical Monofocal Lens

To compare the in vitro performance of the Rayone EMV (Rayner) intraocular lens (IOL), which has a patented aspheric anterior surface and inner optic zone that induces controlled positive spherical aberration, with the Acrysof MA60AC (Alcon), a standard positive spherical monofocal 3-piece IOL using the NIMO TEMPO (Lambda-X) interferometry device.

Rothschild Foundation Hospital, Paris, France.

The NIMO TEMPO device was used to perform wavefront acquisitions of RayOne EMV 20.5D and Acrysof MA60AC 20D for four different apertures, ranging from 2 to 5mm with a 1mm interval, on an ISO 11979-2 model eye. The lenses were then tested with four different positive corneal spherical aberrations (SA) models (0, 0.1, 0.2, 0.3, and 0.4μm). The through-focus Modulation Transfer Function (MTF) of the flat IOL meridian was calculated, and the peaks of MTF value at 50 lp/mm were recorded. The Total Depth-of-Focus (TDOF), defined as the dioptric range in which the MTF value at 50 lp/mm is higher than 0.15, was also determined for each combination of conditions.

At apertures of 2mm and 3mm with low corneal SA models, the TDOF of the MA60AC and the RayOne EMV lenses were similar. However, at 3mm for high SA models, the TDOF was higher for the MA60AC than the Rayone EMV (1.75D vs. 1.55D and 1.9D vs. 1.6D for SA 0.3 and 0.4 μm). At a 4mm aperture, the TDOF of both lenses remained similar for low corneal SA models, but for high SA models, the Rayone EMV performed better (1.65D vs. 1.25D and 1.7D vs. 1.25D for SA 0.3 and 0.4 μm). At a 5mm aperture, the TDOF of both lenses decreased. Regarding the MTF peak, both IOLs showed a significant decrease in the MTF peak with increasing aperture and SA value. The MTF peak of the Rayone EMV was either lower or equal to the MTF peak of the MA60AC in all conditions.

Both the MA60AC and the RayOne EMV showed an important decrease in MTF in large aperture and high SA corneal models. The aspheric design of the RayOne EMV, with its enhanced central positive spherical aberrations, appeared to provide a better depth of focus than the MA60AC with a large aperture. However, this advantage was accompanied by a slight decrease in contrast compared to the MA60AC, as well as a deterioration of optical quality at 3mm in the high SA corneal models. These results need to be compared to in-vivo performance of both lenses.