To evaluate the theoretical effect of decentration of aspherical intraocular lenses (IOLs) and wavefront-corrected IOLs up to the sixth order on higher-order aberrations (HOAs) (third through sixth order) of the eye.
An aspherical IOL with HOAs of fourth-order spherical aberrations only (−0.287 μm with a 6-mm pupil) and a wavefront-corrected IOL with HOAs of equal magnitude and opposite from the corneal HOAs were created and laterally shifted up to 1 mm to simulate decentered IOLs. The residual HOAs for pupils of 3 to 6 mm were calculated by combining the HOAs from the cornea and the decentered IOL. Based on the residual HOAs, optical quality was rated by 3 criteria: the Marechal criterion, a diffraction-limited optical system with an aberration less than λ/14; P10, the lower 10th percentile of the corneal HOAs in this study group; and decreased HOA, residual ocular HOAs less than the corresponding corneal HOAs.
Simulated implantation of the aspherical IOLs and wavefront-corrected IOLs was performed in 154 eyes of 94 patients aged 40 to 80 years. For a centered aspherical IOL and a 6-mm pupil, no eyes met the Marechal criterion, and the P10 and decreased-HOA criteria were met by 46% and 93% of eyes, respectively. For a 6-mm pupil, the required centration was 0.47 mm to meet the decreased-HOA criterion in 50% of eyes. With a wavefront-corrected IOL and a 6-mm pupil, the centrations required to meet the criteria for 90% of eyes were 0.04 mm for the Marechal criterion, 0.36 mm for P10, and 0.48 mm for the decreased-HOA criterion.
Excellent centration is required to maximize the visual outcome of wavefront-corrected IOLs.
With current surgical techniques, implantation of aspherical IOLs and wavefront-corrected IOLs will reduce total ocular HOAs below corneal HOAs in approximately 45% and 86% of eyes (6-mm pupil), respectively.