Extended pneumocephalus occurring in subdural, subarachnoid and intraventricular space due to blunt head trauma.
In this case, a large amount of air occupies the subdural space at the level of the frontal lobes, between the tips of the frontal lobes giving the appearance of Mount Fuji, thus suggesting tension pneumocephalus.
There is also the appearance of mild brain swelling on both hemispheres.
Intracranial air entrapment in the form of small bubbles is seen diffusely in the subarachnoid space and in several cisterns (‘‘air bubble sign’’), with a preference at the left side of the brain. Air has also filled part of the left lateral ventricle.
On the bone window, an extended fracture of the left temporal and sphenoid bone is seen, crossing the midline up to the right lateral wall of the sphenoid sinus, which is opacified by hyperdense (haemorrhagic) material.