Internal spherical aberration by ray tracing-type aberrometry in multifocal pseudophakic eyes

Purpose To demonstrate the results of the ray tracing-type aberrometer in measuring spherical aberration (SA) in pseudophakic eyes with monofocal intraocular lens (IOL), aspheric monofocal IOL, or aspheric diffractive multifocal IOL. Methods Total, corneal, and internal SA were measured using iTrace at a 6-mm pupil size in 27 eyes of 27 patients implanted with a monofocal spherical IOL (group 1: Natural, SN60AT), 30 eyes of 30 patients implanted with a monofocal aspheric IOL (group 2: IQ, SN60WF), and 30 eyes of 30 patients implanted with a multifocal aspheric IOL (group 3: ReSTOR, SN6AD1) at 3 months after cataract surgery. We compared the internal SAs of these IOLs in pupil sizes of 3, 4, 5, and 6 mm. Results There were no demographic statistically significant differences among the groups. The internal SA of group 1 had a positive value. The internal SA of group 2 was −0.175±0.135 μ m in 5-mm pupils and −0.227±0.253 μ m in 6-mm pupils. The internal SA of group 3 was −0.072±0.128 μ m in 5-mm pupils and −0.173±0.231 μ m in 6-mm pupils. Conclusion Measuring internal SA with iTrace yields relatively accurate results in all types of IOLs with adequate pupil sizes.