General Remarks

Neuroimaging in acute encephalopathy in childhood

Jun-ichi Takanashi
Department of Pediatrics, Kameda Medical Center

Abstract

　　Acute infectious encephalopathy, including influenza associated encephalopathy, is more frequently observed in Japanese infants. Acute encephalopathy is divided into at least six types : Reye syndrome, acute necrotizing encephalopathy (ANE) ; hemorrhagic shock and encephalopathy syndrome ; clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) ; encephalopathy with acute brain swelling ; and a recently reported acute encephalopathy syndrome characterized by biphasic seizures and late reduced diffusion (AESD). MRI is accepted as a more sensitive technique than CT for the diagnosis of encephalitis/encephalopathy ; diffusion weighted images are particularly useful for detecting early changes in the brain. In this issue, we review the clinical and radiological features in patients with ANE, AESD, and MERS.

Keywords：Acute encephalopathy, Acute necrotizing encephalopathy (ANE), Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD), Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS).