Accuracy of astigmatism correction with toric intraocular lens implantation in eyes with previous radial keratotomy

Abstract

Purpose: To evaluate refractive outcomes of toric intraocular lens (IOL) implantation in eyes with previous radial keratotomy (RK). Setting: Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Design: Retrospective case series Methods: Consecutive cases with previous RK and had undergone cataract surgery with Toric IOL implantation and met these criteria were retrospectively reviewed: (1) regular bowtie corneal astigmatism within the central 3.0-mm zone, (2) difference in corneal regular astigmatism magnitude between the IOL Master and Lenstar of ≤ 0.75 D, and (3) difference in the regular astigmatism meridians from the 2 biometers of ≤ 15 degrees, and (3) available postoperative manifest refraction at ≥ 8 weeks with corrected distance visual acuity of 20/30 or better. Vector analysis was used to assess the preoperative corneal and postoperative refractive astigmatism. Results: In 40 eyes of 31 patients with previous RK, preoperatively the mean magnitude of corneal regular astigmatism was 2.10 ± 0.98 diopters (D), 1 (3%) and 2 (10%) eyes had anterior corneal regular astigmatism ≤0.5 D and ≤1.0 D respectively, and the centroid value was 1.14 D @ 179° ± 2.05D. Postoperatively, the mean magnitude of refractive regular astigmatism was 0.46 ± 0.44D (D), 29 (73%) and 35 (88%) of eyes had refractive regular astigmatism ≤0.5 D and ≤1.0 D respectively, (P<0.05), and the centroid value was 0.12 D @ 173° ± 0.63 D (P<0.05). Conclusions: Toric IOLs can be used successfully to treat corneal regular astigmatism in eyes with previous RK.