Detection and treatment of optic nerve sheath meningioma.

Optic nerve sheath meningioma is an uncommon tumor of middle age. Patients most often present with progressive visual loss, mild proptosis, and, occasionally, ocular motility defect. With modern neuroimaging, these tumors are relatively easy to diagnose. However, the computed tomography scan or magnetic resonance imaging scan obtained must be a high-resolution study focused on the optic nerve. Clinical observation may be appropriate for patients with relatively preserved vision. However, when vision deteriorates, fractionated stereotactic radiotherapy is indicated and can often restore or preserve visual function.