Purpose To investigate the effect of spherical intraocular lens (IOL) on ocular spherical aberration and its dependency on IOL power.
Methods Wavefront aberrations were measured using a Hartmann-Shack aberrometer (WASCA Analyzer, Zeiss) for forty-seven patients (60 eyes) implanted with four different types of spherical IOLs (Acrysof SA60AT, Sensar AR40e, XLSTABI, or QUATTRO SE) and 19 patients (31 eyes) with aspheric IOLs (MC X11 ASP) at 3 months after cataract surgery. Zernike spherical aberration of a 5.0mm diameter pupil area was derived from the wavefront measurements. Correlation between the spherical aberration and IOL power was statistically analyzed for each group.
Results Mean spherical aberration for the spherical IOL group was 0.163 ± 0.065μm, which was significantly greater than that for the aspheric IOL group (0.017 ± 0.077μm) (t=9.5329, P<0.0001). Spherical aberration in the spherical IOL group was significantly correlated to IOL power (r=0.4578，P=0.0002), while no such significant correlation was found for the aspheric IOL group (r=0.2148，P=0.2459).
Conclusions Spherical IOL design produces more positive spherical aberration in the post-operative eyes than the aspheric design, and the augmented spherical aberration increases with IOL power. The results suggest that in practice of cataract surgery aspheric lens implantation is necessary not only for compensating corneal spherical aberration but also for reducing the positive spherical aberration induced by the lens itself, especially for the eyes a high IOL power is needed. |
