Visual acuity and contrast sensitivity in eyes implanted with aspheric and spherical intraocular lenses

Abstract

Purpose: To compare visual acuity and contrast sensitivity (CS) in eyes implanted with aspheric and spherical intraocular lenses (IOLs) after cataract surgery.

Design: Randomized, prospective study.

Participants: Five hundred twenty-four eyes from 262 cataract surgery patients implanted with 2 IOL models: the AcrySof IQ (262 eyes) and AcrySof SN60AT (262 eyes; Alcon Laboratories, Fort Worth, TX).

Methods: High-contrast photopic best-corrected distance visual acuity (BCVA) and CS under photopic (85 cd/m(2)) and mesopic (6 cd/m(2)) conditions were measured. Pupil diameter was analyzed for distance vision under both lighting conditions. Follow-up was carried out for 6 months in all patients.

Main outcomes measures: Best-corrected distance visual acuity and photopic and mesopic CS after implantation under monocular and binocular conditions.

Results: No statistically significant differences in BCVA were found between either IOL (0.06+/-0.06 and 0.05+/-0.07 logarithm of the minimum angle of resolution units for AcrySof SN60AT and AcrySof IQ groups, respectively; P = 0.091). One hundred percent of patients achieved BCVA of 20/32 or better in both groups. The percentage of patients who achieved BCVA of 20/25 or better was 86.3%. The AcrySof IQ IOL group showed better monocular and binocular CS at 6, 12, and 18 cpd under photopic conditions and at 3, 6, 12, and 18 cpd under mesopic conditions (P<0.001).

Conclusions: Eyes implanted with the aspheric AcrySof IQ IOL showed better photopic and mesopic CS at medium and high spatial frequencies than eyes implanted with the spherical AcrySof SN60AT IOL. High-contrast photopic BCVA was similar between both IOLs.

Financial disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.