Visual performance of 2 aspheric toric intraocular lenses: comparative study

Abstract

Purpose: To compare the visual and aberrometric outcomes of 2 aspheric toric intraocular lenses (IOLs).

Setting: Fatebenefratelli e Oftalmico Hospital, Milan, Italy.

Design: Prospective randomized comparative study.

Methods: Astigmatic patients had cataract surgery with implantation of an Acrysof SN6AT IOL (Group A) or an AT Torbi 709M IOL (Group B). The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, net refractive astigmatism, spherical equivalent (SE), IOL misalignment, and optical quality were evaluated 3 months postoperatively.

Results: The study included 72 eyes. No statistically significant difference was found in UDVA, CDVA, residual refractive astigmatism, intraocular or total higher-order aberrations (Z(n,i) (order of aberrations calculated: 3≤n≤8), coma Z(3,±1), or trefoil Z(3,±2). The UDVA was 0.3 logMAR or better in all eyes and 0.1 logMAR or better in 55.5% of eyes in Group A and in 61.1% of eyes in Group B. Considering polar value analysis, 94.4% of eyes in both groups had a refractive astigmatism value within ±0.50 diopter at KP90 (polar value along 90-degree meridian). The SE was closer to emmetropia in Group A (P=.01). Intraocular lens misalignment of less than 5 degrees was present in 61.1% of cases in Group A (maximum 9 degrees) and in 66.6% in Group B (maximum 11 degrees). Spherical aberration Z(4,0) was significantly lower in Group B.

Conclusions: Both IOLs had similar clinical effectiveness in term of astigmatism correction, rotational stability, and optical quality. Eyes in Group A appeared significantly nearer to emmetropia, while the IOL in Group B induced significantly less spherical aberration.

Financial disclosure: No author has a financial or proprietary interest in any material or method mentioned.