Optic Neuritis

What is it?

Acute or subacute vision loss, usually monocular
Often periocular pain made worse with eye movement
Sometimes optic disc swollen, but fundus exam often normal
Afferent pupil defect usually present
Enhancement (bright signal) of affected optic nerve with MRI contrast agent, and sometimes...
High signal abnormalities elsewhere in brain that reflect multifocal demyelination

In primary demyelinating optic neuritis, high-dose intravenous methylprednisolone 1 gm for 3 days followed by oral prednisone 1 mg/kg for 11 days slightly hastens recovery, but...
Spontaneous total or near total visual recovery occurs in 85%, and...
Corticosteroid treatment does not affect final visual outcome or long term incidence of multiple sclerosis
In optic neuritis associated with other autoimmune disorders, corticosteroid treatment may be very effective
In optic neuritis associated with infections, treatment directed at those infections