Optic pathway tumors. A review with proposals for clinical staging.

Neoplasms of the optic nerves and pathways usually present during the first decade of life with loss of visual acuity. Neurofibromatosis is frequently associated with optic nerve tumors. Computed tomography has improved the capability of diagnosis, exact anatomic delineation of the mass, and clinical follow-up of afflicted patients. The tumors are typically slow-growing, low-grade astrocytomas. Posterior lesions involving the chiasm and hypothalamus may produce considerable morbidity and eventual mortality. Timing and appropriate methods of therapeutic intervention continue to be controversial. Symptomatic patients with blindness and involvement of a single optic nerve may be managed with surgical intervention alone. Posterior lesions with symptomatic progression should be treated with radiation therapy and with cerebrospinal fluid diversion when hydrocephalus occurs. Because these lesions evolve slowly, patients experience prolonged survival, and the benefits of radiation therapy are inconclusive. Clinical staging systems should consider both the functional status of patients and the anatomic extent of the disease.