Case Report: Anti-myelin Oligodendrocyte Glycoprotein (MOG) Positive in a Patient Presented with Orbital Apex Syndrome.

A 60-year-old man presented with no light perception, ptosis and ophthalmoplegia in the right eye. The right fundus examination showed marked optic disc swelling. Serological tests for infectious and infiltrative diseases were all negative. Serum aquaporin-4 antibodies were negative, but anti-myelin oligodendrocyte glycoprotein (MOG) antibodies were positive. Magnetic resonance imaging revealed an extensive lesion in the right optic nerve with abnormal enhancement in the right orbital apex. His vision and eye movements improved after corticosteroid therapy. This report attests to the wide clinical phenotype possible in anti-MOG disease, including orbital apex syndrome.