Presentation
PEA arrest. Neurological deterioration. Asymmetric pupils.
Patient Data
![](https://prod-images-static.radiopaedia.org/images/22134046/044af4f19389014bbda7bb25bf702c_big_gallery.jpeg)
There is global loss of grey-white differentiation, with effacement of the basal cisterns and Sylvian fissures, as well as the sulci of both cerebral convexities. Inferior descent of the cerebellar tonsils. Symmetrical curvilinear hyperdensity in the basal cisterns as well as the sulci over both cerebral convexities (pseudo-subarachnoid hemorrhage sign).
The cerebellum appears relatively hyperdense compared to the supratentorial brain (white cerebellum sign).
Conclusion:
Findings in keeping with severe global hypoxic-ischemic brain injury, with new tonsillar herniation.
Case Discussion
Nice example of pseudo-subarachnoid hemorrhage sign, due to generalized cerebral edema resulting in hypoattenuation of parenchyma, and concomitant thrombosis/distension of vessels.