Acute Necrotizing Encephalopathy in an Infant: Observations by CT, Contrast-Enhanced MRI and Diffusion MRI. A Case...

Acute necrotizing encephalopathy is characterized by bilateral necrotic, hemorrhagic lesions which occur symmetrically in the thalami, dorsal brainstem and dentate nuclei. Development of an extensive breakdown of the blood-brain barrier in the prominent lesions of acute necrotizing encephalopathy was demonstrated in a seven-month-old boy with the disorder, within 14 h after hospitalization by an initially negative post-contrast CT scan, and subsequently positive post-contrast T1-weighted MRI. Diffusion MRI demonstrated concomitant cytotoxic and vasogenic edema in the lesions. By the fortieth day, the lesions apparently regressed with remaining hemorrhagic material in the thalami.