Subdural hematoma often develops as a complication after a head injury. Acute subdural hematoma progresses rapidly, with symptoms usually appearing within 24 hours of the injury. Rapid deterioration occurs thereafter. Subacute subdural hematoma usually develops symptoms within 2 to 10 days after the injury because of a slightly slower leakage of blood into the subdural area. Typically, symptoms of the original injury improve for a period, followed by development of symptoms of subdural hematoma.
Subdural hematoma occurs in people of all ages.
Chronic subdural hematoma occurs in about 1 out of 10,000 people. Minimize the risk of head injury by using appropriate safety equipment and safety precautions in sports or recreation and work. For example, use hard hats, bicycle or motorcycle helmets, and seat belts. Do not dive into water if the depth of water is unknown or if rocks may be present under the surface of the water. Consult the health care provider promptly for any head injury that results in even a brief loss of consciousness , or if other symptoms are present after head injury even without loss of consciousness.