What is the primary cause of epidural hematoma?

The primary cause of an epidural hematoma is the rupture of the middle meningeal artery. This type of hematoma typically occurs following a head injury, often due to a skull fracture that affects the temporal region where the middle meningeal artery runs. When this artery is torn, blood accumulates between the skull and the dura mater, leading to increased intracranial pressure and characteristic symptoms.

Epidural hematomas are often described as having a "lens-shaped" appearance on imaging studies because of their biconvex shape that does not cross suture lines, unlike subdural hematomas, which are more crescent-shaped and can extend across sutures. The clinical presentation often includes loss of consciousness followed by a "lucid interval," where the patient appears fine before experiencing a rapid decline in neurological status as the accumulated blood compresses brain tissue.

In summary, the rupture of the middle meningeal artery is specifically associated with epidural hematomas, making this response the correct choice for understanding this type of condition.