Treatment-related disseminated necrotizing leukoencephalopathy with characteristic contrast enhancement of the white matter.

This report describes unique contrast enhancement of the white matter on T1-weighted magnetic resonance images of two patients with disseminated necrotizing leukoencephalopathy, which developed from acute lymphoblastic leukemia treated with high-dose methotrexate. In both patients, the enhancement was more pronounced near the base of the brain than at the vertex. Necropsy of the first case revealed loss of myelination and necrosis of the white matter. Possible mechanisms causing such a leukoencephalopathy are discussed.