Imaging US: — Early see diffusely increased parenchymal echogenicity of white matter — Later see increased echogenicity in basal ganglia
Imaging CT: — Usually not seen until 6-12 hours post injury — Findings can be subtle so look at sulci at vertex — Loss of gray matter white matter differentiation and loss of cortical sulci — Loss of basilar cisterns — Decreased size of ventricles — Herniation of cerebellar tonsils and uncus — Cerebrum is lower density than normal density of cerebellum – (dense cerebellum sign or cerebellar reversal sign – a sign of diffuse brain injury) — Pseudo subarachnoid hemorrhage — Imaging MRI: — DWI: Diffuse restricted diffusion in cortex and basal ganglia
DDX:
Complications: Brain herniation
Treatment: Craniectomy
Clinical:
Radiology Cases of Diffuse Cerebral Edema
Radiology Cases of Diffuse Cerebral Edema Due to Trauma
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.Axial CT with contrast of the brain shows diffuse brain swelling causing loss of the normal gyral pattern and compression of the ventricular system.Axial CT without contrast of the brain shows acute hemorrhage around the Circle of Willis and brainstem (left) and in the posterior horns of the lateral ventricles bilaterally (right). There is also loss of the cortical sulci and basilar cisterns.Axial CT without contrast of the brain obtained initially (left) shows loss of delineation of the cortical sulci and ventricular system. Axial CT without contrast obtained two days later (right) now also shows a round focus of hyperdensity at the right parietal gray matter white matter junction.
Radiology Cases of Diffuse Cerebral Edema Due to 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.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.
Radiology Cases of Diffuse Cerebral Edema Due to Ruptured Intracranial Aneurysm
Axial CT without contrast of the head (above) shows a round mixed density lesion just to the right of the third ventricle along with diffuse subarachnoid hemorrhage and cerebral edema. Axial (below left) and sagittal (below right) CT angiogram shows the lesion to arise from the A1 segment of the right anterior cerebral artery.
