Spherical aberration after implantation of an aspheric versus a spherical intraocular lens in high myopia

To compare visual performance and wavefront aberration in high myopia implanted with an aspheric intraocular lens (IOL) and a spherical IOL.

In this prospective investigation, 31 highly myopic patients were randomized to receive two IOL types: aspheric IOL (Acri.Smart 36A, 22 eyes) and spherical IOL (Rayner Superflex 620H, 23 eyes). Complete ophthalmological examination including best-corrected visual acuity (BCVA) and corneal aberration (Humphrey corneal topography) were performed preoperatively, 1 and 3 months postoperatively. Ocular aberration (WASCA wavefront analyser) was performed 1 and 3 months postoperatively. Contrast sensitivity under different lighting condition (CSV-1000) was performed 3 months postoperatively.

The aspheric IOL group and the spherical IOL group did not differ in baseline characteristics, including corneal spherical aberration Z(4) (0) (for 5-mm pupil diameter 0.13 +/- 0.06 vs. 0.15 +/- 0.08 microm, P = 0.317; for 6-mm pupil diameter 0.30 +/- 0.11 vs. 0.29 +/- 0.13 microm, P = 0.764). Compared with the spherical IOL group, the aspheric IOL group showed statistically significant less induction of Z(4) (0) of total ocular aberration at a pupil size of 5 and 6 mm 3 months postoperatively (0.07 +/- 0.06 vs. 0.12 +/- 0.06 microm, P = 0.017; 0.17 +/- 0.11 vs. 0.27 +/- 0.12 microm, P = 0.010), but not for 4-mm pupil (0.03 +/- 0.04 vs. 0.02 +/- 0.04 microm, P = 0.54). The BCVA and contrast sensitivity were not statistically different between the two groups postoperatively.

The aspheric IOL induces significantly less spherical aberration than the spherical IOL after implantation in high myopia. Implantation of an aspheric IOL may reduce spherical aberration in high myopia, but clinically superior vision is not achieved.