There are several types of traumatic brain injuries that can result from head trauma: 1. Epidural hematoma occurs when a skull fracture ruptures a meningeal artery, resulting in blood accumulating between the dura and skull. It appears as a biconvex mass on CT scan. 2. Subdural hematoma occurs when bridging veins are damaged, resulting in blood accumulating between the dura and arachnoid. It appears as a crescent-shaped mass on CT scan. 3. Contusions and lacerations are bruises and tears of brain tissue that appear as low-density regions on CT scan.

3. Material to read later-Layers of the Meninges

21. Summary Epidural hematoma (left) in which rupture of meningeal artery, usually associated with a skull fracture, leads to accumulation of arterial blood between the dura and the skull. In a subdural hematoma (right), damage to bridging veins between the brain and the superior sagittal sinus leads to the accumulation of blood between the dura and the arachnoid.

23. CONTUSSION Acute cerebral contusion, there are low-density edema with flake high-density shadow(Asterisk) , accompanied with subarachnoid hemorrhage in the suprasellar pool, sylvian cistern and around the right falx cerebri(black arrow). The gas in the suprasellar pool indicates basal skull fractures(black arrowhead).