title: MR and CT imaging patterns in post-varicella encephalitis.
abstract: The aim of the investigation was to determine the patterns of cerebral involvement on computed tomography (CT) and magnetic resonance (MR) imaging in post-varicella encephalitis. Four children between the ages of 2 and 11 years presented over a 5-year period with a diagnosis of post-varicella encephalitis. Their imaging studies and clinical data were reviewed retrospectively. The medical histories of all four children were noncontributory except for recent bouts of chickenpox 1 week to 3 months prior to hospitalization. Three children presented with parkinsonian manifestations. Bilateral, symmetric hypodense, nonenhancing basal ganglia lesions were found on CT. These areas showed nonenhancing low signal intensity on T1-weighted images and high signal intensity on T2-weighted images on MR. One child presented with diffuse, multiple gray and white matter lesions of similar imaging characteristics; some lesions, however, did enhance. This child had no gait disturbances. Post-varicella encephalitis can produce two patterns of dramatic CT and MR findings. With an appropriate history and clinical findings, varicella as a cause of bilateral basal ganglia or diffuse cerebral lesions can be differentiated from other possible etiologies which include trauma, anoxia, metabolic disorders and demyelinating diseases.
authors.affiliation: Division of Neuroimaging, Children's Memorial Center, Northwestern University Medical School, Chicago, IL 60614, USA.
authors.forename: C F
authors.initials: CF
authors.lastname: Darling
authors.forename: M B
authors.initials: MB
authors.lastname: Larsen
authors.forename: S E
authors.initials: SE
authors.lastname: Byrd
authors.forename: M A
authors.initials: MA
authors.lastname: Radkowski
authors.forename: P S
authors.initials: PS
authors.lastname: Palka
authors.forename: E D
authors.initials: ED
authors.lastname: Allen
mesh_terms: D002644:Chickenpox / Q000150:complications*; D002648:Child; D002675:Child, Preschool; D018792:Encephalitis, Viral / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed