Blurred vision and pain in the eye.

Subacute unilateral visual impairment accompanied by pain on eye movement is characteristic of optic neuritis. Most cases of optic neuritis resolve spontaneously, and acute treatment with intravenous steroids hastens recovery but does not alter the ultimate visual outcome. Brain magnetic resonance imaging (MRI) may permit a diagnosis of multiple sclerosis (MS) to be made after a single clinical demyelinating event such as optic neuritis. Current evidence supports the introduction of disease-modifying therapy in patients with a single clinical event such as optic neuritis and brain MRI compatible with MS. The diagnosis of MS is a confronting life event associated with significant personal, social and financial burdens. The diagnosing neurologist should provide a detailed explanation of the disease and its clinical spectrum and introduce the patient to the wide range of support services, educational material and MS clinics.