Comparison of pseudophakic visual quality in spherical and aspherical intraocular lenses.

OBJECTIVE

This study compares the visual performance of spherical and aspherical intraocular lenses (IOLs) by measuring higher-order aberration and contrast sensitivity (CS) values.

DESIGN

Prospective controlled study.

PARTICIPANTS

Fifty-seven patients with age-related cataract (61 eyes).

METHODS

Patients were randomly allocated to 1 of 3 groups and implanted with either aspherical IOLs, Acrysof IQ (SN60WF) or Tecnis Z9001, or a spherical IOL, Acrysof Natural. Patients underwent routine examinations, including visual acuity, slit-lamp checks, and best-corrected visual acuity (BCVA), as well as measurement of higher-order aberrations and CS values, preoperatively and at 1 week, 1 month, and 2 months postoperatively.

RESULTS

All the patients had a BCVA better than 20/30 postoperatively. The spherical aberrations of the IQ group and Tecnis group were both lower than in the Natural (control) group (IQ: p < 0.05; Tecnis: p < 0.05); there was no significant difference in coma and higher-order aberration. No statistically significant difference was found in spherical aberration, coma, or higher-order aberration between the IQ and Tecnis groups. Under glare conditions, the CS values of the 2 aspherical IOLs were obviously better (IQ: p < 0.05; Tecnis: p < 0.05) than the CS value of the spherical IOL group at low frequency (IQ: 6.3 degrees, Tecnis: 4.0 degrees); under non-glare conditions there was a significant difference in CS values between the aspherical IOL groups and the control group (IQ: p < 0.01; Tecnis: p < 0.01) at low frequency (both 6.3 degrees). There was no statistical difference between the IQ and the Tecnis groups with or without glare.

CONCLUSIONS

An aspherical IOL can effectively reduce spherical aberration after cataract surgery, enhance CS values, and improve visual quality compared with traditional spherical IOLs for age-related cataract. However, there was no statistically significant difference in postoperative aberration and CS values between the Acrysof IQ and Tecnis Z9001 aspherical IOLs.