T2-highlighted U-fibres and rapid parenchymal volume loss in AESD: An under-recognised subtype of paediatric acute encephalopathy syndromes.

Acute Encephalopathy with Reduced Subcortical Diffusion or AED is a unique subtype of acute paediatric encephalopathy which presents with altered mental status, prolonged seizures and developing characteristic radiological signal changes within the subcortical white matter. Reports of such cases have mainly been from Japan (Takanashi, 2009) and this radiological finding has been recognised as a novel feature of AED. We present three paediatric cases from a tertiary paediatric neurosciences centre in Manchester (Royal Manchester Children's hospital) with characteristic subcortical signal change, and furthermore, follow up imaging which in all 3 patients demonstrated a varying degree of cerebral atrophy. We recommend that children presenting with prolonged seizures should be considered for MR imaging ideally after 48hours if clinically stable, and early MR imaging follow-up (at 2-3 months) be performed routinely in patients with AED to assess for presence and degree of parenchymal volume loss for prognostication and to start neuroprotective therapy.