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Magnetic resonance imaging of leukemic invasion of the optic nerve.

As treatment regimens for acute leukemia continue to improve, patients are relapsing more frequently with tumor involvement of the central nervous system. 1 The central nervous system provides a sanctuary for leukemic cells because of the poor penetration of chemotherapeutic agents across the blood-brain barrier. Consequently, with prolonged patient survival, late invasion of the optic nerve by neoplastic cells is no longer a rare clinical manifestation of leukemia. Computed tomography has been a rather insensitive method for detecting abnormalities in patients with leukemic infiltration of the optic nerve. Although in some patients it has shown a thickened optic nerve shadow or enhancement of the perioptic meninges after contrast administration, in other patients it has revealed nothing. 2,3 We provide the first description of the magnetic resonance findings in a patient with presumed leukemic invasion of the optic nerve. Report of a Case. —A 58-year-old man developed fever, lethargy, and gingival