Chronic Epidural Hematoma Caused by Traumatic Intracranial Pseudoaneurysm of the Middle Meningeal Artery: Review of the Literature with a Focus on this Unique Entity

Abstract

Pseudoaneurysms of the middle meningeal artery represent fewer than 1% of all intracranial aneurysms; it can be associated with different patterns of intracranial hemorrhages. A chronic epidural hematoma (CEDH) caused by post-traumatic pseudoaneurysm of the middle meningeal artery (MMA) has not yet been reported. A 17-year-old male patient was referred to our unit after a car accident, with head trauma and presented motor and language deficits. After a brain computed tomography scan that revealed a left temporal epidural hematoma, the patient underwent surgery with complete hematoma drainage and recovery. After 5 months, he developed a chronic epidural hematoma secondary to a pseudoaneurysm of the MMA, as shown by cerebral angiography. We also reviewed the literature to evaluate the state of the art concerning the diagnosis and management of patients affected by CEDH. Pseudoaneurysms are considered unstable because of the poor support of the aneurysmal wall. They tend to progressively increase in size and ultimately rupture, leading to delayed intracranial bleeding. A univocal definition of the interval of time between the acute head trauma and the diagnosis to classify the CEDH is still debated. To our knowledge, this is the first case described of a CEDH secondary to a pseudoaneurysm of the MMA. In our study we suggest defining CEDHs as extradural hematomas diagnosed and/or treated 21 days or more after a head injury.