Patients aged 18-65 with acute demyelinating optic neuritis where treatment with high dose corticosteroids are already been chosen by the patient and the diagnosing physician will be contacted for screening and enrollment. Patients will then be randomized to receive equivalent doses of either intravenous (IV) or oral corticosteroid treatment. Optic nerve function assessments will be compared at baseline, prior to treatment, one and six months post corticosteroid treatment. This will allow for a comparison on whether the route of medication plays a role in the effectiveness of treatment with high dose corticosteroids.