Findings
The CT scans demonstrate a left frontal epidural hematoma.

Discussion
Epidural hematomas arise in the potential space between the dura and the skull and do not cross sutural margins; the bleeding is mostly due to rupture of the middle meningeal artery. The major cause for EDH is trauma and skull fractures are present in 75 to 95 percent of patients. Epidural bleeds produce a bi-convex (lens-shaped) hematoma on CT because the collection is limited by dural attachments at the cranial sutures.


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