Nonarteritic Anterior Ischemic Optic Neuropathy NAION A Misnomer

The fact that vascular abnormalities such as disc hemorrhages and swelling are present at the time of visual loss in NAION, followed by peripapillary vascular narrowing and ensuing disc pallor is enticing, but not etiologically conclusive for ischemia. There is both optic disc as well as retinal evidence that whiteness with disc swelling is indicative of axoplasmic stasis (cotton wool spots) that may also occur simply from anatomic distortion of axons rather than occlusion of vessels.1 It may also occur from mechanical stretching and fracture of the axonal cytoskeleton 2 and frank membrane disruption with axoplasmic leakage.'