MRI of central nervous system abnormalities in childhood leukemia.

PURPOSE To document the imaging abnormalities seen in the central nervous system (CNS) in childhood leukemia or as complications of its treatment. MATERIALS AND METHODS Magnetic resonance imaging (MRI) of 15 children with neurologic complications of leukemia or its treatment were reviewed retrospectively. The first group consisted of patients with CNS abnormalities detected prior to or during treatment, or within three months after completion of treatment. Patients with CNS complications detected by MRI three months following completion of treatment were included in the second group. RESULTS Among the 15 children, six had two or more different CNS abnormalities. The imaging abnormalities seen in 12 patients prior to or during treatment, or within three months after completion of treatment included orbital, temporal, cerebellopontine angle, and spinal chloroma; bilateral subdural hematoma in the subacute stage; multifocal intraparenchymal hemorrhage; bilateral retinal hemorrhage and detachment; hematoma in the pons and mesencephalon; PRES (posterior reversible leukoencephalopathy syndrome); bilateral leukemic infiltration of the 3(rd), left 7(th), and 8(th) cranial nerves; and meningeal leukemia. Three months after completion of treatment, three patients had CNS complications including radiation necrosis and secondary brain tumor, osteomyelitis of the L3 vertebra, and meningeal leukemia. CONCLUSION The wide spectrum of CNS abnormalities that occur during and after treatment for leukemia is related to leukemia and to the treatment method. Because many neurologic complications of leukemia are treatable, early diagnosis is essential.