BRV retinal occlusion. Ophthalmoscope view of the retina of the eye, showing occlusion of the branched retinal vein (BRV). Retinal occlusion is the blockage of one or more blood vessels of the retina. Blockage can be seen as a yellow occlusion in the vein at bottom right. This will lead to haemorrhage (bleeding) of the vein resulting in a loss of vision. The branched retinal vein passes from the surface of the retina through the yellow optic disc (at left) and out of the eyeball. Occlusion may be caused by atherosclerosis: fat deposits on the vein walls due to high cholesterol levels.