Delayed intracerebral tension pneumocephalus--report of two cases.

Two patients were found with delayed intracerebral tension pneumocephalus 5 and 12 months later, following head injury. Simple skull X-ray showed a large air-containing cyst in the left frontal lobe in both cases. Dural repairs were done through an intradural approach via single frontal craniotomy. Basal skull fracture with dural tear at cribriform plate of ethmoid bone and intracerebral cyst filled with air were found during operation. Their deteriorated consciousness became clear post-operatively. Plain computed tomography was a very useful instrument in determining the location of the gas collection, fracture site, and tension on the brain.