Optical behavior of the eye implanted with extreme intraocular lens powers

To evaluate the induced ocular aberrations after cataract surgery with extreme low- powered and high-powered spherical monofocal intraocular lenses (IOLs) using a new pyramidal wavefront sensor aberrometer.

Vissum Instituto Oftalmológico, Alicante, Spain.

Prospective observational comparative study.

This study included patients who had cataract surgery with implantation of a spherical monofocal IOL. The patients were divided into three groups according to the IOL power. Group 1: +20 diopters (D) to +23 D; Group 2: less than +10 D; and Group 3: +29 D or more. Assessment after 3 months included: uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, contrast sensitivity function test (Ginsburg), corneal aberrometry, and total ocular aberrometry with a pyramidal wavefront sensor aberrometer (Osiris) for 4.0 mm, 4.5 mm, and 5.0 mm pupil diameters.

The study comprised 88 eyes of 56 patients. There were no differences between all groups in terms of refractive error, corneal aberrometry, or total ocular higher-order aberrations at any analyzed pupil diameter. The ocular spherical aberration (SA) was not significantly different between groups with a 4.0 mm pupil. The SA was significantly lower in Group 2 when compared with Group 1 and Group 3 for both 4.5 mm (P = .01 and P = .001, respectively) and 5.0 mm (P = .002 and P = .002, respectively). There was no significant difference in SA between Group 1 (+20 D to 23 D) and Group 3 (≥+29 D) at any analyzed pupil diameter. Higher SA did not correlate to lower contrast sensitivity.

Despite the theoretical evidence, only a negligible amount of clinically insignificant aberrations were induced by high-powered positive IOLs. Low-powered IOLs did not induce significant levels of SAs.