Reversible optic neuritis secondary to paranasal sinusitis.

Three patients are described in whom optic neuritis was presumably caused by concurrent sinus infection. Aggressive treatment of the underlying sinus condition led to prompt visual improvement. Although underrecognized in clinical neurology, paranasal sinusitis is an uncommon but treatable cause of optic neuritis. Shortcomings of conventional radiological investigations and inappropriate use of corticosteroids may contribute to initial misdiagnosis.