Diagnostic work-up in central retinal artery occlusion and ischemic optic neuropathy - what is important?

Ischemia of the retina in central retinal artery occlusion (CRAO) and of the optic nerve in ischemic optic neuropathy (ION) are common causes of irreversible vision loss in elderly patients and require a thorough diagnostic work-up. First and foremost, giant cell arteritis should be confirmed or ruled out. The further work-up of non-arteritic CRAO and non-arteritic ION (nAION) aims to determine the cardiovascular risk profile. Patients with nAION should be screened for sleep apnoea. In non-arteritic CRAO, the search for embolic sources is the most important diagnostic task. A "white spot sign" seen on transorbital ultrasound confirms the diagnosis of embolic CRAO and rules out an arteritic etiology of CRAO.