A traumatic giant posterior cerebral artery aneurysm mimicking a tentorial edge meningioma.

Traumatic intracranial aneurysms due to non-penetrating trauma are rare. Commonly they are associated with an overlying fracture or secondary to trauma against the falcine edge in the case of the distal anterior cerebral artery. To date, only one case of traumatic posterior cerebral artery aneurysm has been reported associated with a comminuted depressed occipital fracture and lacerated transverse sinus. We report a case of a giant traumatic aneurysm of the posterior cerebral artery P2 branch directly associated with the tentorial edge. Its mechanism of formation is analogous to the falcine distal anterior cerebral artery aneurysms.