Teaching NeuroImages Neurology Resident and Fellow Section A 32-year-old woman presented with headaches, ataxia, diplopia © 2015 American Academy of Neurology

Nerrant et al. Ten days after respiratory infection, a 32-year-old woman presented with headaches, ataxia, diplopia without encephalopathy. Brain MRI revealed extensive white matter, brainstem and cerebellar vasogenic edema, without gadolinium enhancement, partially regressive during follow-up (Figure A). CSF revealed transient elevated protein level (1.01g/L) and hypercellularity (123 neutrophils/mm 3 ). Symptoms resolved within ten days without treatment. 18 FDG ‑ PET showed bilateral temporo-parieto- occipital and cerebellar hypometabolism (Figure B). © 2015 American Academy of Neurology Vignette

T0 D10 M12 A FLAIRADC M1 B Nerrant et al. © 2015 American Academy of Neurology Imaging

Negative anti-GQ1b but positive anti-GD1a IgG led to the diagnosis of Bickerstaff’s brainstem encephalitis (BBE). Neurologists should be aware that diffuse brain hypometabolism and/or vasogenic edema can be associated with BBE 1,2. Extensive vasogenic edema in Bickerstaff’s brainstem encephalitis Nerrant et al. © 2015 American Academy of Neurology