Brushing Against the Tentorium: Traumatic Pseudoaneurysm of the Posterior Cerebral Artery

Excerpt

Both blunt and penetrating traumatic brain injury (TBI) may cause damage to the intracranial vasculature. Blunt force brings about sudden deceleration, and injury may develop in arteries that are in the anatomic vicinity of the falx, tentorium, or bone. Displacement of brain tissue and its vasculature allows arteries to brush against these hard surfaces. This injury causes a wall hematoma and rapidly creates ballooning of the outer layer of the artery, also known as a pseudoaneurysm. The aneurysm is unstable and may rupture, usually after some asymptomatic time interval. These intracranial pseudoaneurysms are at different sites (most commonly the pericallosal branches of the anterior cerebral artery, followed by branches of the middle cerebral artery and the posterior cerebral artery). These aneurysms remain an unusual complication of blunt TBI. In contract, penetrating injury (often from shrapnel) can damage any cerebral artery and in a series including penetrating injury traumatic aneurysms were also found in the cavernous portion of the carotid artery and presenting with epistaxis [1]. …