[A case of post-traumatic pseudoaneurysm on the posterio meningeal artery].

A case is reported of post-traumatic delayed appearance of a pseudoaneurysm on the posterior meningeal artery. In the immediate post-traumatic stage, the patient had mild disturbance of consciousness, mild subarachnoid hemorrhage, and mid-line skull fracture of the posterior cranial fossa. At 15 hours after the trauma, the patient suddenly developed deep coma and respiratory arrest. CT scanning showed further spreading of the subarachnoid hemorrhage and newly detected subdural hemorrhage. After the patient regained spontaneous respiration, cerebral angiography was performed 24 hours after admission. This initial angiography showed no aneurysm, but at 17 days after the trauma, follow-up angiography demonstrated the delayed appearance of an aneurysmal dilatation on the posterior meningeal artery. The aneurysm was resected surgically and proved to be a pseudoaneurysm. Having developed normal pressure hydrocephalus afterwards, the patient received a V-P shunt, and was discharged 150 days after the trauma with no major neurological deficit. We discussed the indication for and timing of angiography for detecting pseudoaneurysms. Posterior meningeal artery pseudoaneurysms should be resected surgically, because intravascular surgery through the vertebral artery involves considerable risk of embolic complications.