Diffuse Cerebral Edema

Etiology: hypoxic ischemic encephalopathy
Imaging: usually not seen until 6-12 hours post injury
— CT: cerebrum is lower density than normal density of cerebellum
— MRI: diffuse cortical and basal ganglia restricted diffusion

Cases of Diffuse Cerebral Edema

CT of cerebral edema and subarachnoid hemorrhage — Axial CT without contrast of the brain shows diffuse low density through the bilateral cerebral hemispheres (anteriorly) with a normal density cerebellum (posteriorly) that appears relatively hyperdense when compared to the cerebral density. Subarachnoid hemorrhage was also seen bilaterally in the basal cisterns.

CT of subgaleal hematoma, diastatic skull fracture, depressed skull fracture, cerebellar contusion, diffuse cerebral edema in child abuse — Axial CT without contrast of the brain shows high density material in the subgaleal tissues posteriorly, a wide lucency in the right posterior skull along with two areas of depressed lucency in the left frontal skull, a rounded high-density lesion in the midline of the cerebellum, and decreased density of the cerebrum when compared to the normal density of the cerebellum along with loss of the normal gray matter-white matter differentiation.

CT of diffuse cerebral edema in child abuse — Axial CT without contrast of the brain shows normal density in the rounded top of the cerebellum (in the center of the left image) compared to the diffuse low-density throughout the cerebrum. There is obliteration of the basal cisterns and loss of the normal gray matter-white matter differentiation. There is also a small left sided high density extra-axial cresenteric fluid collection that tracks medially along the entire falx.