Intraocular Lens Exchange due to Incorrect Lens Power
Received 17 April 2006; accepted 4 July 2006. published online 21 November 2006.
Purpose
To evaluate patients who had intraocular lens (IOL) exchange for unexpected postoperative refractive errors, determine the sources associated with the errors, and derive an empiric approach to estimating the power for IOL exchange.
Design
Retrospective review of interventional case series.
Participants
Twenty-two eyes that underwent IOL exchange for correcting unexpected refractive errors after cataract surgery with IOL implantation were reviewed.
Intervention
All the IOLs for IOL exchange were placed in-the-bag. The same type of IOLs was used for original IOL implantation and IOL exchange in 91% (20/22) of eyes.
Main Outcome Measures
Uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), refraction, and reasons for IOL exchange. The equation derived from refractive change and change in IOL power was developed to calculate IOL power for exchange.
Results
Of the 22 cases, the identified reasons were keratometry errors in 5 (23%) and incorrect axial length (AL) determination in 3 (14%). In 3 other cases, a wrong IOL was implanted. After IOL exchange, 82% (18/22) of eyes were within ±0.50 diopters (D) and 86% (19/22) within ±1.00 D of emmetropia. Uncorrected visual acuity was 20/40 or better in 82% of eyes, and BSCVA was 20/40 or better in 95% (21/22) of eyes. The correlation between change of refraction and IOL power was significant (P<0.002).
Conclusions
Among the identified causes, incorrect corneal power determination was the most frequent reason for incorrect IOL power implantation, followed by error in AL measurement and inserting a wrong IOL. The pre-exchange refraction can be used theoretically to calculate the IOL power for exchange.
Correspondence to George J. C. Jin, MD, PhD, Eye Institute of Utah, 755 East 3900 South, Salt Lake City, UT 84107.
Manuscript no. 2006-438.
Dr Crandall is a consultant for Alcon Laboratories Inc. and is with the Speaker Bureau for Advance Medical Optics Inc. and Bausch and Lomb. No other author has financial interest in any material mentioned.
ABSTRACT