Abstract
Purpose :
An accurate postoperative refraction is the main goal of cataract surgery. We performed a chart review to identify factors associated with changes in refraction in the first month after surgery.
Methods :
A retrospective chart review identified 205 patients (249 eyes) who underwent surgery at the Moran Eye Center in Salt Lake City, UT by two surgeons from 3/1/15-6/30/16. 44 underwent sequential bilateral surgery. Age, sex, presence of dry eye, biometry data, intended target refraction (iTR), intraocular lens (IOL) model, use of limbal relaxing incisions (LRIs) and manifest refraction (MRx) at one week (W1) and one month (M1) were recorded. One-piece acrylic monofocal IOLs by Alcon and Abbott Medical Optics were included. Eyes with other visually significant pathology, surgical complications, visual acuity of 20/40 or worse and lost to follow-up outside the specified date ranges were excluded.
For statistical analysis two groups were formed: eyes that achieved within 0.25D spherical equivalent (SE) from the iTR vs. eyes >0.25D from the iTR. Two comparisons were considered: M1 SE to iTR and W1 to M1 SE. Univariate tests for differences between the two groups were performed using a chi-square test. Multivariable logistic regression were performed on the outcome of >0.25D absolute deviation (AD) for each of the three comparisons. Covariates in the multivariable models were age, sex, anterior chamber depth, axial length, dry eyes, LRIs and the mean of corneal curvature K1 and K2 (Kmean).
Results :
Based on the chi-square test, there were significantly more eyes with a M1 MRx >0.25D SE from the iTR that had a toric IOL (14%) than in the <0.25D group (4.8%) p=0.023. In the multivariable logistic regression analysis for each of the comparisons to predict AD >0.25D from the iTR, Kmean was a marginally significant predictor (Odds ratio [OR]:1.19, 95% CI:1-1.43, p=0.055) for M1 SE to the iTR. LRIs were a significant predictor (OR:2.04, 95% CI:1.01-4.12, p=0.047) for W1 to M1 SE.
Conclusions :
Patients who received toric IOLs were more likely to have a MRx at M1 that was >0.25D SE from the iTR. Patients who received LRIs or had steeper corneal curvature were more likely to have a MRx >0.25D SE from the iTR from W1 to M1 and from the iTR to M1, respectively. Analysis predicting the accuracy of the 2nd eye based on the accuracy of the 1st eye are forthcoming.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.