CT perfusion illustrated reversal of uncal herniation after placement of an external ventricular drain

Compression of the PCA in the context of uncal herniation is usually deducted in retrospect only with presence of a demarcated infarction in the respective territory. In this particular case with early recovery of oculomotor nerve function after CSF drainage, additional CT perfusion was able to directly document both significant compromise of the PCA as well as effective reversal of uncal herniation with restitution of perfusion within the PCA territory