JLE

Epileptic Disorders

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Presentation, diagnosis and treatment of bilateral Rasmussen's encephalitis in a 12-year-old female Volume 15, issue 3, September 2013



Figure 1 A) Initial CT scan obtained in 2007 (over four years prior to seizure onset). Note moderate right cerebellar volume loss (arrow). No other abnormality was identified. There was no evidence of left hemispheric volume loss. B) Head CT obtained at seizure onset in June 2011 demonstrated right cerebellar volume loss, which progressed slightly relative to the previous CT examination (arrow). Volume loss in the left cerebral hemisphere was identified, predominantly involving the frontal and anterior parietal lobe near the vertex. C) MRI obtained one month later (axial T2 FLAIR) demonstrated left hemispheric volume loss, right cerebellar volume loss, and increased signal consistent with gliosis (arrowhead), and regions of increased signal in the left hemispheric cortex and subjacent white matter (arrows). The right cerebral hemisphere was normal. D) MRI obtained with worsening daily seizures involving the left arm and leg (axial T2 FLAIR). New signal abnormality was noted in the right posterior frontal lobe involving the medial precentral gyrus and paracentral lobule (arrowhead). Persistent signal abnormalities were noted in the left hemisphere (arrows). Right cerebellum volume loss and signal were stable. E) FDG-PET performed the next day, with continued seizures, demonstrated a region of localised hypermetabolism (arrowhead) in the right posterior medial frontal lobe corresponding to the signal abnormality in (D). Regions of moderate to marked hypometabolism were noted in the left hemisphere and right cerebellum (arrows). F) MRI obtained after bilateral frontal biopsies, plasmapheresis, rituximab, and steroids (axial T2 FLAIR). Biopsy sites were identified in areas of previously noted signal abnormalities in the posterior frontal lobes at the vertex (arrows). Signal abnormality on the right decreased. Other areas of left hemispheric signal and right cerebellar volume loss were stable.



Figure 2 Representative EEGs from December 2011 (A and B: seizure+45 seconds; transverse montage) and January 2012 EEG showing evolution (C: average montage, see next page) of the patient's seizures from focal onset at Pz-P4 to EPC centred over Pz.



Figure 3 Bilateral brain biopsies demonstrated dural fibrosis without inflammation. Similar changes were observed in right and left frontal grey and white matter. Gliosis was evident with the presence of gemistocytic astrocytes (A) and inflammatory infiltration, composed of CD3 positive T-lymphocytes (C) and CD68 positive microglia (D). The inflammatory cells were seen scattered in the parenchyma and around blood vessels. CD20 positive B-lymphocytes were not identified. A microglial nodule was seen in the left frontal white matter (B). A few red neurons and neurons with chromatolysis were present. No dysmorphic or balloon cells were identified.