Purpose: To prospectively examine changes in the central visual field (VF) in patients with advanced open-angle glaucoma (OAG) with advanced late stage after trabeculectomy for 12 months.
Design: Prospective interventional case series.
Methods: In all, 27 eyes of 27 OAG patients at a single center with a best-corrected visual acuity (BCVA) of ≥40/200 and a mean total deviation of test locations of the 10-2 program of the Humphrey VF analyzer of ≤-20 dB preoperatively were enrolled. Intraocular pressure (IOP), VF parameters of the 10-2 program, and BCVA were examined for 12 months after trabeculectomy with mitomycin C. Slopes of VF parameters and their correlation with presumed risk factors were studied.
Results: IOP decreased from 19.7±5.8 to 9.7±2.6 mm Hg (P<0.001) over postoperative 1 year. The slopes of all VF parameters did not significantly differ from zero (P>0.33), and none of the presumed factors significantly correlated with the slopes of those parameters (P>0.14). There were two eyes (7%) and one eye (4%) with ≥2 lines of deterioration in BCVA (decimal fraction) at 1 and 12 months, respectively, after surgery with no apparent causes.
Conclusions: Trabeculectomy resulted in little change in the central 10-degree VF, but significant decrease in BCVA without apparent causes might occur approximately 5% of the cases.