Central Retina Vein Occlusion (CRVO) is a common retinal vascular disorder. Clinically, CRVO presents with variable visual loss; the fundus may show retinal hemorrhages, dilated tortuous retinal veins, cotton-wool spots, macular edema, and optic disc edema.
Kooragayala, Lakshmana M., M.D., Central Retinal Vein Occlusion. Medscape (updated June 29, 2016), http://emedicine.medscape.com/article/1223746-overview