The central artery of the retina enters the eyeball in the middle of the optic nerve and then divides into branches which radiate from this centre. The artery is a branch of the anterior cerebral, and it and its branches are end-arteries. Embolism is met with in cases of valvular disease of the heart. There is sudden blindness, which is usually permanent at least to the extent of the portion of the retina corresponding with the distribution of the occluded artery. The retina in the area affected undergoes necrosis and softening, this process being sometimes accompanied by haemorrhage. Ultimately the optic nerve becomes atrophied.

Thrombosis of the retinal artery or vein is also known to occur.