eradiology

Epidural Hematoma on CT scans

http://eradiology.bidmc.harvard.edu/Classics/item.aspx?section=Neuroimaging&labelpk=84a3cf36-44c2-4370-9522-50369eb830e3&pk=e56ebea9-dcd1-44d4-9aea-bd6bfe3df54e

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.

Epidural Hemorrhage

Findings
The CT scans show a lens-shaped, biconvex high attenuation collection in the posterior left parietal lobe exerting mass effect.

Discussion
Acute bleeds present with high attenuation on CT. Epidural hematomas are due to traumatic head injuries which causes bleeding between the inner table of the skull and the dura. The majority are in the temporo-parietal region where a skull fracture causes damage to the middle meningeal artery or one of its branches. EDHs may cross the midline but do not cross suture lines.


http://eradiology.bidmc.harvard.edu/Classics/item.aspx?section=Emergency+Radiology&labelpk=33f0adab-853f-4010-a0e2-0756b3f1eac5&pk=c1634e61-5022-4bf4-8648-111c7af88cc3

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.


http://eradiology.bidmc.harvard.edu/Classics/item.aspx?section=Emergency+Radiology&labelpk=33f0adab-853f-4010-a0e2-0756b3f1eac5&pk=e56ebea9-dcd1-44d4-9aea-bd6bfe3df54e

Epidural Hematoma

Epidural Hematoma
An epidural hematoma is usually associated with a skull fracture. It often occurs when an impact fractures the calvarium. The fractured bone lacerates a dural artery or a venous sinus. The blood from the ruptured vessel collects between the skull and dura. On CT, the hematoma forms a hyperdense biconvex mass. It is usually uniformly high density but may contain hypodense foci due to active bleeding. Since an epidural hematoma is extradural it can cross the dural reflections unlike a subdural hematoma. However an epidural hematoma usually does not cross suture lines where the dura tightly adheres to the adjacent skull.

Biconvex (lenticellular) epidural hematoma (arrowheads),deep to the parietal skull fracture (arrow).