Middle meningeal artery trauma.

We present the case of a patient who had the symptoms of a subarachnoid hemorrhage but was subsequently found to have an unusual combination of a separate traumatic pseudoaneurysm and a traumatic arteriovenous fistula of the middle meningeal artery. A review of the literature revealed a difference in the clinical course of patients with traumatic pseudoaneurysms compared to that of patients with arteriovenous fistulas. Patients who were found to have traumatic pseudoaneurysms of the middle meningeal artery frequently manifested signs of delayed hemorrhage. This mechanism may account for the prolonged lucid intervals exhibited in some patients subsequently found to have epidural hematomas.