The Relative Frequency of Severe Vision Loss from CRAO Versus NAION

Sudden, painless monocular vision loss is a diagnostic challenge in the acute setting. The two most common vascular causes of acute monocular vision loss in the elderly are central retinal artery occlusion (CRAO) and nonarteritic anterior ischemic optic neuropathy (NAION) whose evaluation and treatment greatly differ. There are currently no consensus diagnostic or treatment guidelines for patients presenting with acute monocular vision loss. According to a national survey, up to 53% of US institutions offer intravenous tissue plasminogen activator (tPA) for CRAO, which can sometimes occur without an eye examination in centers that lack access to an on-call ophthalmologist. Therefore, in this study, we aimed to describe the relative frequency of patients with CRAO vs. NAION that presented with acute painless monocular severe vision loss using a population-based cohort.