Pseudoexfoliation Glaucoma as a Predictor of Refractive Surprise After Uneventful Cataract Surgery.

Abstract

The pseudoexfoliation glaucoma group produced higher mean absolute error (MAE) and higher percentages of large-magnitude prediction error, in all investigated intraocular lens formulas. Postoperative anterior chamber angle and change in intraocular pressure (IOP) were associated with absolute error. The purpose of this study is to evaluate refractive outcomes of cataract surgery in patients with pseudoexfoliation glaucoma (PXG) and to determine the predictive factors for refractive errors. Fifty-four eyes with PXG, 33 eyes with primary open angle glaucoma (POAG) and 58 normal eyes undergoing phacoemulsification, in Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey, were included in this prospective study. The follow-up was 3 months. Preoperative and postoperative anterior segment parameters measured by Scheimpflug camera were compared after adjusting for age, sex, and axial length. The mean prediction error, MAE, and percentages of large-magnitude prediction error (>±1.0D) in SRK/T, Barrett Universal II, and Hill-RBF formulas were compared. There was a significantly greater anterior chamber angle (ACA) enlargement in PXG eyes compared with POAG ( P =0.006) and normals ( P =0.04). The PXG group showed significantly higher MAE in SRK/T, Barrett Universal II, and Hill-RBF (0.72, 0.79, and 0.79D, respectively) than POAG (0.43, 0.25, and 0.31D, respectively) and normals (0.34, 0.36, 0.31D, respectively) ( P <0.0001). The large-magnitude error was significantly more frequent in the PXG group among the 3 groups with SRK/T (37%, 18%, and 12%, respectively) ( P =0.005), Barrett Universal II (32%, 9%, and 10%, respectively) ( P =0.005), and Hill-RBF (32%, 9%, and 9%, respectively) ( P =0.002). The MAE was correlated with postoperative ACA and IOP decrease in Barrett Universal II ( P =0.02 and 0.007, respectively) and Hill-RBF ( P =0.03 and 0.02, respectively). PXG may be a predictor for refractive surprise after cataract surgery. Prediction errors may be due to IOP-lowering effect of surgery and larger postoperative ACA than expected, in the presence of zonular weakness.