Effect of preoperative corneal astigmatism orientation on results with a toric intraocular lens

PURPOSE: To compare the Acrysof IQ toric intraocular lens (IOL) and the Acrysof IQ aspheric nontoric IOL and evaluate the effect of preoperative corneal astigmatism orientation on results. SETTING: Department of Ophthalmology, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan. DESIGN: Comparative case series. METHODS: This retrospective chart review comprised patients with cataract and preoperative corneal astigmatism between 1.0 diopter (D) and 2.5 D having toric IOL (toric group) or aspheric nontoric IOL (nontoric group) implantation. Eyes were grouped depending on the preoperative axis of corneal astigmatism; that is, with the rule (WTR), against the rule (ATR), and oblique. Preoperative and postoperative analyses included uncorrected (UDVA) and corrected (CDVA) distance visual acuities and cylindrical power preoperatively and 3 months postoperatively. RESULTS: The postoperative CDVA was not significantly different between the 2 IOLs; however, the postoperative UDVA was significantly better in the toric group than in the nontoric group (P<.0001). The postoperative residual cylindrical power was significantly smaller in the toric group (P<.0001). In eyes with ATR and oblique astigmatism, the mean postoperative UDVA was significantly better in the toric group, whereas there were no differences between the 2 groups in patients with WTR astigmatism. CONCLUSIONS: There was significant improvement in postoperative cylinder and UDVA with toric IOLs compared with nontoric IOLs. With a superior corneal incision, the benefits of astigmatism correction with the toric IOL were more significant in patients with ATR and oblique astigmatism than in those with WTR astigmatism. (C) 2013 ASCRS and ESCRS