Retinal vasculitis. Ophthalmoscopy view of the retina of the eye, showing retinal vasculitis. At centre is the yellow optic disc, the point where the optic nerve and retinal blood vessels (red) enter the eye. Of the blood vessels the veins appear darker red. Retinal vasculitis is the inflammation of the retinal blood vessels, usually the veins. Sheathing of the veins (breakdown of the vein walls) typically occurs, seen as unclear vein outlines. There is also bleeding (haemo- rrhage) visible as patches of red. Retinal vasculitis is usually a sign of systemic diseases such as syphilis, toxoplasmosis, sarcoidosis or systemic lupus erythematosus.