The advent of OCT angiography is making it easier for researchers and clinicians to better understand blood flow dynamics in many ocular diseases, glaucoma included. New research finds a reduction in the foveal avascular zone (FAZ) and enhanced perifoveal microcirculation after IOP-lowering surgery. The study, published in the British Journal of Ophthalmology, noted that these changes didn’t occur in the non-surgical fellow eye during the follow-up period, which argues in favor of FAZ growth in open-angle glaucoma patients and the mediating influence of surgery.
The investigation included 54 patients with primary open-angle glaucoma who underwent unilateral glaucoma surgery to reduce IOP. Post-surgery, IOP of the study eye significantly decreased from 22.1mm Hg to 10.3mm Hg. The FAZ also faced a significant reduction from 0.485mm2 to 0.446mm2.
However, in the non-surgical fellow eyes, the preoperative and postoperative mean FAZ areas (0.398mm2 and 0.396mm2, respectively) did not significantly differ. The change in the FAZ area significantly correlated with the pre-op area and foveal sensitivity and the change in IOP.
Shoji T, Kanno J, Weinreb RN, et al. OCT angiography measured changes in the foveal avascular zone area after glaucoma surgery. Br J Ophthalmol. November 5, 2020. [Epub ahead of print].