title: MRI in methotrexate-related leukoencephalopathy: Disseminated necrotising leukoencephalopathy in comparison with mild leukoencephalopathy.
abstract: We report two fatal cases of methotrexate (MTX)-induced disseminated necrotising leukoencephalopathy (DNL) in which MRI was repeated from the onset. Initial T2-weighted images showed multiple areas of high signal, mainly in deep cerebral white matter, which on follow-up, spread and coalesced to involve the entire white matter. Small irregular low-signal foci on T2-weighted images were seen within the high-signal lesions. Multiple areas of contrast enhancement corresponded to these low-signal foci. The condition of both patients deteriorated and they died. We compared their MRI findings with those of seven patients with mild MTX-related leukoencephalopathy, six of whom were asymptomatic; one had transient neurological symptoms. They showed no contrast enhancement, but rather mild-to-moderate diffuse high signal in deep white matter, which later disappeared. These findings suggest that multiple low-signal foci on T2-weighted images with contrast enhancement may be characteristic of DNL, and that contrast-enhanced imaging is useful to differentiate this condition from mild leukoencephalopathy.
authors.affiliation: Department of Radiology, Hokkaido Graduate University School of Medicine, 060-8638, Sapporo, Japan. okamasak@luke.or.jp
authors.forename: M
authors.initials: M
authors.lastname: Oka
authors.forename: S
authors.initials: S
authors.lastname: Terae
authors.forename: R
authors.initials: R
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Sawamura
authors.forename: K
authors.initials: K
authors.lastname: Kudoh
authors.forename: K K
authors.initials: KK
authors.lastname: Tha
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: M
authors.initials: M
authors.lastname: Kaneda
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Miyasaka
mesh_terms: D000293:Adolescent; D001927:Brain Diseases / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D064420:Drug-Related Side Effects and Adverse Reactions; D004673:Encephalomyelitis, Acute Disseminated / Q000175:diagnosis / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D007968:Leukoencephalopathy, Progressive Multifocal / Q000139:chemically induced* / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008727:Methotrexate / Q000009:adverse effects*; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects
chemical_list: D008727:Methotrexate