Optic Neuritis & Demyelinating Disease

Optic neuritis (ON) is acute inflammatory demyelination of the optic nerve and the single most exam-relevant link between Ophthalmology and Neurology. The classic teaching is painful monocular visual loss with a relative afferent pupillary defect (RAPD), dyschromatopsia, and a central scotoma — and in the retrobulbar variant, a normal-looking disc, hence "the patient sees nothing and the doctor sees nothing." Opti…