Clinical comparison of the optical performance of aspheric and spherical intraocular lenses

PurposeTo compare the optical performance of aspheric Tecnis ZA9003 and spherical Sensar AR40e intraocular lenses (IOLs).SettingLaboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.MethodsAn aspheric IOL was implanted in 1 eye and a spherical IOL in the other eye of patients with bilateral age-related cataract. Contrast sensitivity was measured using 2 computerized tests (vertical sine-modulated gratings and circular sine-modulated patterns) with cycloplegia and a 5.0 mm artificial pupil under photopic conditions at optimum refractive correction and at several defocus levels. The depth of focus and the myopic shift (shift of optimum focus toward more myopic values at lower spatial frequencies) were determined. Higher-order aberrations were assessed using a Hartmann-Shack wavefront analyzer; straylight was measured with a straylight meter.ResultsIn the 60 eyes evaluated, there were no statistically significant differences in contrast sensitivity measured at optimum focus, depth of focus, or straylight between the 2 IOLs. The mean spherical aberration was significantly lower with the aspheric IOL (−0.036 μm) than with the spherical IOL (0.064 μm) (P<.001) and the mean myopic shift, statistically significantly smaller (0.05 diopter [D] and −0.47 D, respectively) (P<.001).ConclusionsEyes with the aspheric IOL had lower spherical aberration than eyes with the spherical IOL and, related to that, a smaller myopic shift. No significant differences were found between the 2 IOLs in contrast sensitivity measured at optimum focus, depth of focus, or straylight.Financial DisclosureNo author has a financial or proprietary interest in any material or method mentioned.