Tumors of the optic nerve and chiasm.

Optic nerve gliomas and meningiomas, which remain puzzling to clinicians, are reviewed with special attention to natural history, magnetic resonance findings, and appropriate management. New histopathological insights established the true neoplastic nature of optic nerve gliomas considered by most clinicians to be benign hamartomas. Unusual presenting manifestations and therapeutic alternatives of optic glioma have been also considered. Since the association of optic nerve gliomas and meningiomas with neurofibromatosis has long been recognized, special attention has been drawn to clinical, genetic, and ophthalmologic aspects of neurofibromatosis. New and unusual presenting manifestations, diagnostic and treatment opportunities concerning optic nerve involvement in metastatic disease, and lymphomatous proliferation are also described.