Optic nerve head vascular variations in pseudoexfoliative and primary open-angle glaucoma

Abstract

Purpose: The purpose of this study was to assess the optic nerve head microvascular changes in pseudoexfoliative and primary open-angle glaucoma and define the relationship between vessel density and retinal nerve fiber layer thickness. Methods: This observational cross-sectional study assessed 72 eyes with primary open-angle glaucoma, 41 eyes with pseudoexfoliative glaucoma, and 60 healthy eyes. On the basis of optic nerve head-centered, 4.5 mm × 4.5 mm scan size images, we evaluated the vessel density, as well as the peripapillary sector, inside disk, and all sectoral quadrants. Results: Both glaucoma Groups had lower vessel density in all regions compared with the healthy Group (p<0.05 for all variables). Vessel densities of the nasal inferior, inferior nasal, and inferior temporal sectors in both glaucoma Groups showed similar results (p=0.157, p=0.128, p=0.143, respectively). Eyes with pseudoexfoliative glaucoma had significantly lower vessel densities than eyes with primary open-angle glaucoma in all other regions (p<0.05 for all variables). For both glaucoma Groups, the average retinal nerve fiber layer thickness positively correlated with vessel density in all peripapillary sectors (p<0.05 for all variables). Conclusions: Reduction in vessel density correlated with the thinning of retinal nerve fiber layer in both glaucoma Groups. Decreased vessel density in the optic nerve head can be used to demonstrate the microvascular pathologies and possible ischemic changes that lead to faster progression and worse prognosis in pseudoexfoliative glaucoma.