Abstract
Purpose :
To compare the effect of phacoemulsification on intraocular pressure (IOP) and visual field mean deviation in patients with primary open angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG)
Methods :
A prospective observational comparative study conducted at the Glaucoma Department of the Association to Prevent Blindness in Mexico. This study enrolled consecutive patients having routine phacoemulsification with intraocular lens (IOL) implantation. In Group 1 we included POAG patients and Group 2 of PXG patients. Mean deviation (MD) obtained by standard automated perimetry was used to determine the severity of glaucoma. Data about IOP values and number of glaucoma medications used was collected at baseline, 1, 3, 6 and 12mo postoperatively.
Statistical analysis: The estimated study sample size was 88, determined given an α of 0.05, a β of 0.20, a standard deviation of 1.00, and a power of 0.80. The statistical significance of changes in IOP was determined using a Student t-test or a Wilcoxon matched pairs signed rank test depending on data distribution. The comparison among time intervals was assessed by the Kruskal-Wallis test. In addition, a Dunn multiple comparison test was used to compare the preoperative IOP measurements with postoperative time intervals. A p value less than 0.05 was considered statistically significant. Normal and non-normal distributions were determined by Shapiro- Wilk tests for all variables. Statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) software (version 20).
Results :
35 patients from 63 to 95 years (mean 77) were included. After phacoemulsification there was a statistically significant reduction in IOP values compared to baseline in both POAG and PXG patients at all postoperative time intervals (P<0.001). PEX group showed a greater decrease in IOP compared to POAG, although not statistically significant (p=0.096). The mean postoperative change in IOP (ΔIOP) between groups, number of glaucoma medications used and the severity of glaucoma (MD) will be analyzed when the data is complete. (December 2018)
Conclusions :
In both types of glaucoma, phacoemulsification result in a significant IOP reduction over a 12-month follow-up period compared to baseline.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.