Which imaging finding is characteristic of an epidural hematoma?

Which imaging finding is characteristic of an epidural hematoma?

• A. Subdural hematoma
• B. Intracerebral hemorrhage
• C. Epidural hematoma
• D. Subarachnoid hemorrhage

Answer: (C)

A lens-shaped (biconvex) hyperdense collection between the skull and dura on non-contrast CT is the hallmark of an epidural hematoma. This shape arises from rapid arterial bleeding, classically from the middle meningeal artery, and the hematoma is typically bounded by the cranial sutures, so it does not cross them. This contrasts with subdural hematoma, which is crescent-shaped and can cross sutures, intracerebral hemorrhage which is within brain tissue, and subarachnoid hemorrhage which distributes within the subarachnoid spaces.

A lens-shaped (biconvex) hyperdense collection between the skull and dura on non-contrast CT is the hallmark of an epidural hematoma. This shape arises from rapid arterial bleeding, classically from the middle meningeal artery, and the hematoma is typically bounded by the cranial sutures, so it does not cross them. This contrasts with subdural hematoma, which is crescent-shaped and can cross sutures, intracerebral hemorrhage which is within brain tissue, and subarachnoid hemorrhage which distributes within the subarachnoid spaces.