The structure of human retinal vasculature and interstitium in the terminal stage of primary openangle glaucoma

Purpose: to study the structural organization of the vascular bed of human retina in the terminal stage of primary open-angle glaucoma (POAG).

Material and methods. We performed a comparative immunohistochemical analysis of the content of vessels in the retina of 13 eyes of patients in the terminal stage of POAG, enucleated for medical reasons, and 17 eyes with uveal melanoma, using the markers of blood vessels endothelium CD34. The ultrastructural organization of the interstitium and endothelial cells of retinal microvessels was studied by electron microscopy and morphometry.

Results. A significant increase in the volume density of the interstitium and a decrease in the volume density of CD34+-blood vessels in the retina of patients in the terminal stage of POAG, as compared with uveal melanoma, were revealed. An increased volume density of luminal and basal caveolae and the formation of transendothelial channels in the cytoplasm of endotheliocytes of retinal blood capillaries in the terminal stage of POAG were noted.

Conclusion. In the terminal stage of POAG, the interstitial spaces of the retina are increased and the volume density of blood vessels is dropping. The increased volume density of luminal and basal caveolae and the formation of transendothelial channels in the cytoplasm of blood capillary endotheliocytes indicate the growth of transcytosis and the permeability of the blood-retinal barrier.

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