What is the primary source of bleeding in an epidural hematoma?

The primary source of bleeding in an epidural hematoma is the middle meningeal artery. An epidural hematoma typically occurs when there is a rupture of the middle meningeal artery, often as a result of skull trauma that fractures the temporal bone. This artery runs underneath the skull and is susceptible to injury from blunt force trauma.

When the middle meningeal artery is torn, blood accumulates between the dura mater (the outermost membrane covering the brain) and the skull, leading to an increase in intracranial pressure. This bleeding can occur rapidly, and if not addressed quickly, it can be life-threatening. The characteristic lens-shaped appearance of an epidural hematoma on imaging is due to this accumulation of blood.

Understanding the role of the middle meningeal artery in the formation of epidural hematomas is crucial for recognizing the clinical presentation and determining the urgency of surgical intervention.