Abstract
Purpose:
To evaluate the risk factors and frequency of short-term VF progression after phacoemulsification in patients with glaucoma, specifically evaluating the effect of postoperative IOP spike.
Methods:
Charts of glaucoma patients having phacoemulsification by the same surgeon between January 1999 and May 2013 were reveiewed. Patients included in this study were considered to have stable glaucoma and had at least one Humphrey VF in the 18 months prior to surgery and two VFs during the 2 years after surgery. Visual field progression was defined as a 1) decrease in visual field index (VFI) by three percentage points or 2) at least three points that decreased by 5dB, with at least one point that decreased by 10dB on total deviation (TD) plot or pattern standard deviation (PSD) plot on HVF. The number of eyes with postoperative VF progression was assessed, and risk factors for VF progression were evaluated.
Results:
Of 108 eyes (90 patients) included in the study, 10 (9.3%) progressed by VFI criteria. By TD and PSD criteria, 18 (16.7%) and 20 (18.5%) showed VF progression. Preoperative mean deviation was -7.92 ± 3.71 for eyes that progressed by PSD criteria and -4.23 ± 4.71 for eyes that did not progress (p<0.001). Average postoperative mean deviation was -8.66 ± 3.77 for eyes that progressed and -3.59 ± 5.27 for eyes that did not progress (p<0.001). Eyes that progressed had more myopic preoperative refraction (-3.75 ± 3.31 vs. -1.67 ± 3.64, p=0.019) and were treated with a greater number of glaucoma medications postoperatively (2.40 ± 1.05 vs. 1.83 ± 1.05, p= 0.036). Axial length was similar between the two groups (24.87 ± 1.3 vs. 24.62± 1.58, p=0.46). Preoperative and postoperative IOP measurements did not significantly differ between the two groups. Of the eyes that progressed, 6/20 (30%) had a ≥50% IOP increase postoperatively (IOP spike) compared to 11/88 (12.5%) (p=0.083) in the group that did not progress.
Conclusions:
A significant proportion of glaucoma patients have postoperative visual field progression after phacoemulsification. Postoperatively, there was a trend towards a greater proportion of IOP spike in patients that had visual field progression. Our data demonstrate that patients with more severe disease preoperatively or myopic refraction were more likely to have visual field progression after phacoemulsification.