Subdural hematoma

A subdural haematoma (subdural hematoma) or subdural hemorrhage (SDH) is a form of traumatic brain injury in which blood gathers within the inner meningeal layer of the dura matter (the outer protective covering of the brain). Usually resulting from tears in veins that cross the subdural space, subdural hemorrhages may cause an increase in intracranial pressure (ICP), which can cause compression of and damage to delicate brain tissue. Acute subdural hematoma (ASDH) has a high mortality rate and is a severe medical emergency.

In contrast, epidural hematomas are usually caused by tears in arteries, resulting in a buildup of blood between the dura and the skull.

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