Optic neuritis is vision change or loss due to demyelinization of the optic nerve. Optic neuritis is classically associated with multiple sclerosis.
What is Optic Neuritis?
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Coronal T1 contrast-enhanced fat suppressed magnetic resonance imaging showing enhancement of the left optic nerve (arrow) which is typical of optic neuritis. Optic neuritis: Dooley MC, Foroozan R - Journal of ophthalmic & vision research (2010). Not altered. CC.