Effect of surgical intraocular pressure lowering on peripapillary blood flow in primary open glaucoma patients using optical coherence tomography angiography

Abstract

Objective The aim of this research was to study the effect of intraocular pressure (IOP) lowering after trabeculectomy on peripapillary blood flow and retinal nerve fiber layer (RNFL) thickness using optical coherence tomography angiography.Study design This is a prospective, nonrandomized, single-center, observational study.Patients and methods The study included 18 eyes of 18 patients with primary open angle glaucoma scheduled for trabeculectomy. Using optical coherence tomography angiography, the radial peripapillary vessel density (PVD) and RNFL thickness were quantified before and 1 week after surgery. Changes were calculated as total, superior hemi, and inferior hemi. They were then correlated with the change in IOP.Results One week after surgery, the mean IOP reduction was −14.28±7.70 mmHg (−56.87±14.97%, P=0.000). The mean change in the radial PVD was +0.47±2.48% (P=0.431), and the mean change in RNFL thickness was +0.44±3.36 μm (P=0.582). There was no statistically significant correlation between these changes and the reduction in IOP (r=−0.104, P=0.682, and r=−0.287, P=0.249, respectively).Conclusion There was a nonsignificant increase in the radial PVD and RNFL thickness after IOP reduction with trabeculectomy in primary open angle glaucoma, 1 week after surgery.