Long-term clinical outcomes of toric intraocular lens implantation in cataract cases with preexisting astigmatism

PURPOSE: To evaluate the long-term clinical outcomes and rotational stability of toric intraocular lenses (IOLs) to correct preexisting astigmatism in cataract patients. SETTING: Kitasato University Hospital, Kanagawa, Japan. DESIGN: Prospective observational study. METHODS: Phacoemulsification with implantation of a toric IOL (Acrysof IQ toric SN6AT) was performed in cataract patients with corneal astigmatism. The postoperative follow-up was up to 2 years. RESULTS: This study enrolled 378 eyes of 302 patients with a mean age of 63.4 years +/- 16.9 (SD). The corrected distance visual acuity 3 months postoperatively was 20/25 or better in 94.7% of eyes. The mean refractive cylinder was -1.92 +/- 1.45 diopters (D) preoperatively, -0.59 +/- 0.62 D 3 months postoperatively (322 eyes), and -0.67 +/- 0.90 D at 2 years (73 eyes). There were statistically significant differences between the preoperative and 3-month postoperative measurements (P<.001, Wilcoxon signed-rank test). The mean IOL misalignment was 4.1 +/- 3.0 degrees 2 years postoperatively. The mean IOL rotation was 4.5 +/- 4.9 degrees within 1 day postoperatively. The rotation was more than 20 degrees in 6 eyes, all of which had an axial length (AL) of more than 25.0 mm. All rotations occurred within 10 days postoperatively. CONCLUSIONS: Toric IOLs were effective in reducing preexisting corneal astigmatism and had overall good rotational stability. A large degree of IOL rotation might occur in eyes with a relatively long AL, especially during the early postoperative period. The 6 rotated IOLs were implanted to correct with-the-rule astigmatism.