Correction of astigmatism during cataract surgery: toric intraocular lens compared to peripheral corneal relaxing incisions

Abstract

Purpose: To compare the efficacy of astigmatic correction achieved at the time of cataract surgery using toric intraocular lens (IOL) implantation versus peripheral corneal relaxing incisions.

Methods: A retrospective review assessed the outcomes of phacoemulsification cataract surgery performed between January 2006 and January 2008 by a single surgeon. Patients receiving a toric IOL (toric IOL group) or peripheral corneal relaxing incisions (relaxing incisions group) were included in the study. Main outcome variables included postoperative uncorrected distance visual acuity (UDVA) and manifest refractive cylinder. Each treatment modality was stratified by amount of preoperative keratometric astigmatism into three groups (low, moderate, and high astigmatism) for comparative analysis.

Results: A total of 192 eyes were included in the study; 77 received a toric IOL and 115 received peripheral corneal relaxing incisions. Preoperative data were not significantly different between the two groups except regarding keratometric astigmatism, which was higher in the toric IOL group (P<.05). Average postoperative astigmatism was 0.42 diopters (D) and 0.46 D in the toric and relaxing incisions groups, respectively. In subgroup analysis, no statistical significance separated the two treatment options in terms of amount of surgically induced astigmatism or residual astigmatism. Eyes with astigmatism ≥2.26 D were more likely to achieve 20/40 UDVA from a toric IOL.

Conclusions: Toric IOL implantation and peripheral corneal relaxing incisions yielded similar results regarding surgical correction of astigmatism at the time of phacoemulsification cataract surgery. Both treatment modalities achieved comparable results with mild-to-moderate astigmatism. Higher degrees of astigmatism favor use of a toric IOL.