It is intended to investigate clinically, retinal, optic disc, and uveal vascular occlusive disorders. In (a) ischemic, (b) hemorrhagic, (c) venous stasis retinopathy, and (d) retinal branch vein occlusion, it is our intention to study (1) the natural history of retinal disease in a detailed prospective study, (2) the evolution of the retinal vascular dynamics, and (3) the role of some of the therapeutic regimens in randomized double-masked controlled studies. The role of posterior ciliary artery ischemia (in the optic nerve head, peripapillary choroid and choroid) in glaucoma, low-tension glaucoma, and anterior ischemic optic neuropathy is to be investigated and correlated with optic disc and visual field changes. The role of corticosteroid and/or ocular hypotensive therapy in anterior ischemic optic neuropathy is to be studied on double-masked controlled study. In all these studies, the assessments will be made (1) clinically for the various ocular lesions, (2) by fluorescein angiography for the circulatory disturbance dynamics, and (3) by electrophysiological testing for some of the retinal functions. BIBLIOGRAPHIC REFERENCES: Hayreh, S.S.: Central retinal vein occlusion - differential diagnosis and management. Trans. Amer. Acad. Ophthal. Otolaryng. 1977, in press. Hayreh, S.S., van Heuven, W.A.J., Hayreh, M.S.: Experimental central retinal vascular occlusion. I. Pathogenesis of central retinal vein occlusion. Arch. Ophthal. (Chicago) 1977, in press.