Effect of Intraocular Lens Asphericity on Quality of Vision after Cataract Removal An Intraindividual Comparison

Purpose: To determine the effect of intraocular lens (IOL) asphericity on quality of vision after cataract removal. Design: Intraindividual, prospective, randomized clinical trial. Participants: Twenty-six cataract patients received 2, one-piece, blue-light-filtering hydrophobic acrylic IOLs each. Methods: One eye was implanted with a spherical (SN60AT, Alcon) and the contralateral eye with an aspheric (SN60WF, Alcon) IOL with -0.2 mu m spherical aberration (SA). All trial-specific measurements (corneal topography, wavefront sensing, high-contrast visual acuity [HCVA], contrast sensitivity [CS]) were performed 6 months after surgery. A paired Student t-test or Wilcoxon test was used to check intergroup differences. Main Outcome Measures: Absolute values and intraindividual differences (Delta(i)) of corneal and ocular higher order aberrations and best-corrected visual Strehl ratio based on the optical transfer function (BCVSOTF) values for virtual pupil diameters of 3, 4, 5, and 6 mm were computed. Photopic and mesopic HCVA, photopic, and high-mesopic CS as well as high-mesopic disability glare (DG) were measured using the Frankfurt-Freiburg Contrast and Acuity Test System. Results: No intergroup difference of demographic data, pupillometry, and corneal aberrations were observed. Coma and trefoil root mean square and SA were significantly lower in the aspheric group resulting in higher BCVSOTF, mesopic HCVA, and photopic and high mesopic CS. All A, values with exception of photopic HCVA and DG indicated significantly better performance of the aspheric IOL. Conclusions: An aspheric IOL with -0.2 mu m SA provide higher quality of vision than spherical IOL in terms of retinal image quality, mesopic HCVA and CS.