What are the differences between ischaemic optic neuropathy and retinal artery occulsion?

Difficult to answer: If one distinguishes between anterior and posterior ischemic optic neuropathy this is easier to answer as the former is almost always caused by giant cell arteritis and treated with prednisone and the latter is due to systemic atherosclerosis. Acute central retinal artery occlusion may be caused by carotid occlusion or dissection or cardioembolic events. Treatment includes hyperbaric O2.

Location: Ischemia affecting the anterior optic nerve is due to occlusion of the short posterior ciliary arteries, whereas posterior ischemia is due to occlusion of pial vessels arising from the ophthalmic artery. A retinal artery occlusion is due to blockage of an arteriole inside the eyeball, usually from emboli. Both are serious causes of loss of vision with near similar prognosis but different treatment