Clinical presentation
55 year old gentleman had a cardiac arrest and was resuscitated. Remains unconscious since the event.
MRI

Findings
Global hypoxic insult involving supratentorial neuroparenchyma in the form of diffuse grey matter restriction, involving deep grey matter nuclei as well. Focal hemorrhage in genu of corpus callosum, likely sequelae of anticoagulant therapy. selective sparing of the vital regions of the brain – the posterior fossa is evident with no features of ischemia or infarction.
Discussion
In CT, typically this appears as reverse cerebellar sign, wherein the diffuse hypoattenuation of the supratentorial brain makes the intact cerebellum appear ‘dense’. Global hypoxemia is commonly encountered in children, in adults, most commonly when there is sudden hypovolemia and not enough blood is projected from the heart into the brain.
Read more
- Radiopaedia
- Huang, Benjamin Y., and Mauricio Castillo. “Hypoxic-ischemic brain injury: imaging findings from birth to adulthood 1.” Radiographics 28.2 (2008): 417-439.
- Arbelaez, Andres, Mauricio Castillo, and Suresh K. Mukherji. “Diffusion-Weighted MR Imaging ofGlobal Cerebral Anoxia.” American Journal of Neuroradiology 20.6 (1999): 999-1007.