Traumatic Aneurysm of the Posterior Inferior Cerebellar Artery Caused by Fracture of the Clivus

The authors present a case of traumatic aneurysm of the posterior inferior cerebellar artery produced by fracture of the clivus. Varieties of clival fractures reported in the literature are reviewed. Associated basilar or carotid arterial lesions have been reported, but traumatic aneurysm, so far as we are aware, has not. The authors emphasize the importance of a high index of suspicion of undetected traumatic intracranial aneurysm when an unusual amount of subarachnoid hemorrhage is noted on the initial computed tomographic scan, particularly if associated with displaced basal skull fracture.