Improved refractive outcome for ciliary sulcus-implanted intraocular lenses

Abstract

Objective: To investigate the ideal correction of intraocular lens (IOL) power for sulcus implantation.

Design: Retrospective, comparative case series.

Participants: The records of 679 patients undergoing cataract surgery from June 2007 to June 2008 were reviewed.

Intervention: Eyes in this series underwent phacoemulsification and IOL implantation with local anesthesia. Patients in our study population had their IOL power reduced by 0.5 or 1 diopter (D) from that calculated by the SRK-T formula for in-the-bag implantation. The IOL implanted was the foldable 3-piece acrylic Acrysof MA60AC (Alcon Laboratories Inc., Fort Worth, TX).

Main outcome measures: In each case, the difference between actual spherical equivalent (SE) refraction and that predicted by biometry using the SRK-T formula was calculated.

Results: Posterior capsule tears requiring implantation of IOL in the ciliary sulcus occurred in 36 eyes. When comparing eyes in which the power was reduced by 0.5 D with those in which the reduction was 1.0 D, those with a power reduction of 1.0 D had significantly less unexpected error (0.49 vs. 1.01 D SE). After stratifying eyes by axial length (AL), we found higher unexpected refractive error in short eyes (<22 mm AL). Likewise, eyes with a predicted IOL power >25 D had a greater postoperative refractive error.

Conclusions: This is the first comparative clinical review examining adjustment of power of the sulcus-implanted IOL. We found that the IOL power should be adjusted according to the measured AL and predicted IOL power. For patients with a predicted IOL power from 18 to 25 D, power should be reduced by at least 1 D; for lenses >25 D, power should be reduced by 1.5 to 2 D.