Presentation
History of ALL on intrathecal methotrexate. Presents with acute onset of right hemiplegia, hemisensory loss, and dysarthria 10 days after most recent cycle of chemotherapy.
Patient Data
Oval region of restricted diffusion in the left posterior centrum ovale.
Case Discussion
Methotrexate is a cause of acute neurotoxicity in children with hematologic malignancies. Patients most commonly present with acute onset of hemiplegia or aphasia, often 6-11 days after intrathecal methotrexate administration. Classic imaging finding is restricted diffusion in bilateral or unilateral centrum semiovale. Follow-up imaging in 1-2 months usually shows resolution of diffusion abnormality and development of abnormal signal intensity on FLAIR and T2WI.