No abstract

Purpose The purpose of this study was to explore macula vessel density and foveal avascular zone (FAZ) parameters in exfoliation glaucoma (XFG) compared to primary open-angle glaucoma (POAG) using optical coherence tomography angiography (OCTA). Methods This was a cross-sectional observational study. Twenty-six XFG and 28 POAG patients with comparable visual field defects on Humphrey 24-2 and 10-2 perimetries were recruited. OCTA scans (3 × 3 mm) centered on the fovea were obtained. Built-in software was used to measure superficial capillary plexus (SCP) vessel density at different quadrants of the macula. Custom software was then used to create a full-thickness image. The FAZ was manually delineated, and large vessels were removed. Vessel density in eight concentric rings with increments of 200-μm diameters from the delineated FAZ was measured. FAZ parameters were calculated using the custom software. Results SCP density was significantly lower in the superior (mean difference [MD] = −4.32, 95% confidence interval [CI] = −7.02, −1.61, P = 0.003) and nasal (MD = −3.00, 95% CI = 05.22, −0.77, P = 0.010) quadrants in XFG versus POAG. SCP vessel density using the concentric ring approach revealed significantly decreased values at all eight rings in XFG versus POAG. In the full-thickness analysis, density was significantly less in the XFG group in all rings except the initial 200 μm. No significant differences existed in FAZ parameters between the groups. Conclusions Despite the presence of comparable central visual field defects, the macula vessel density was predominately lower in XFG compared with POAG in our sample of patients. Further studies are warranted to investigate the consistency of our results.

laucoma is a progressive neurodegenerative ocular disease that causes visual field loss owing to damage of the retinal ganglion cells. The most common type of glaucoma in the United States, primary open-angle glaucoma (POAG), 1 has been classified into normal-tension (NTG) and high-tension glaucoma (HTG) based on the cutoff point for the statistical reference range of intraocular pressure (IOP). 2 High-tension glaucoma is associated with various risk factors, such as older age, high IOP, African descent, and positive family history. 3 Exfoliation syndrome (XFS), an age-related systemic condition, is the most common recognizable cause of open-angle glaucoma worldwide, comprising most cases in some countries. 4 Exfoliation syndrome is characterized by the production, deposition, and progressive accumulation of a white fibrillogranular extracellular material (exfoliation material) throughout the anterior segment, most prominently on the anterior lens surface, on the zonules with their resultant weakness, and on the pupillary border. Exfoliation material is also found in posterior segment vessels, including the vortex veins, posterior ciliary arteries, and central retinal vessels. It is observed microscopically in numerous organs, including the skin, heart, lungs, and kidney, primarily in the connective tissue. 5-7 In addition to obstructing fluid pathways, exfoliation material accumulation affects vascular endothelial cells as well as contractile pericytes, which wrap IMPORTANCE Systemic blood flow alterations have been described using video nailfold capillaroscopy (NFC) in high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) variants of primary open-angle glaucoma (POAG). To date, no previous studies have explored alterations in nailfold capillary blood flow in exfoliation glaucoma (XFG). OBJECTIVE To investigate the measure of peripheral blood flow as a surrogate marker of systemic vascular involvement in patients with XFG, HTG, and NTG, as well as in individuals serving as controls, using NFC.

No abstract