[How I explore…optic neuritis].

Optic neuritis is an inflammation of the optic nerve most often caused by autoimmune or systemic disease. The diagnostic management is transdisciplinary. The clinical approach should be global first and then system-oriented. It determines the choice of additional investigations whose purpose is the characterization of the type and the cause of the optic neuritis. The exploration initially involves neuroimaging techniques, visual electrophysiology and biological analyses. Optical coherence tomography is of considerable interest in specifying the differential diagnosis. Diagnostic accuracy influences the treatment and prognosis of this condition.