Comparison of Optical Performance in Eyes Implanted with Aspheric Foldable, Spherical Foldable, and Rigid PMMA IOLs

To compare the optical performance of rigid spherical polymethylmethacrylate (PMMA), foldable spherical, and foldable aspheric intraocular lenses (IOLs).

Measurements were obtained monocularly from pseudophakic patients with a PMMA IOL (Ophtec PC265y or Rayner 105U), spherical AcrySof MA30 IOL (Alcon Laboratories Inc), or aspheric Tecnis ZA9003 IOL (Abbott Medical Optics). Contrast sensitivity was measured using the Holladay automated contrast sensitivity test with 5.0-mm artificial pupil at 3 and 6 cycles per degree at optimal focus and at several defocus levels. The myopic shift (shift of the optimal focus toward more myopic values at lower spatial frequencies) and depth of focus were determined. Wavefront aberrations were assessed with a Hartmann-Shack wavefront analyzer; straylight was measured using the C-Quant meter (Oculus Optikgeräte GmbH).

Nine patients with a spherical rigid PMMA IOL, 19 patients with a spherical foldable IOL, and 24 patients with an aspheric foldable IOL met the inclusion criteria. Eyes with an aspheric IOL showed less spherical aberration than eyes with other IOLs; no differences were found in overall higher order aberrations. No differences in contrast sensitivity at optimal focus and in straylight were found among the IOLs. Eyes with a PMMA IOL showed a larger depth of focus compared to eyes with an aspheric IOL. Eyes with an aspheric IOL had a smaller myopic shift than eyes with other IOLs.

Optical performance differences among the IOLs in this study are small, concurring with similar higher order aberrations found in the three groups. Reduction in myopic shift appears to be the most obvious effect of aspheric IOLs.