Your skull is like a Box. You can only "fit" so much into it. When you introduce blood due to an injury (trauma), the blood has no where to go so this causes pressure on the brain and eventually you...
Bleeding BetweenBleeding beneath the outer sheath covering the brain - called the dura mater.
The hematoma can be confirmed with magnetic resonance imaging (MRI), which is the preferred type of scan;
A subdural hematoma is caused by an injury to the head that tears blood vessels.
Small hematomas that do not cause symptoms may not need to be treated. Otherwise, the hematoma should be surgically removed.