A chronic subdural hematoma is an "old" collection (several weeks after initial injury) of blood and blood breakdown products between the surface of the brain and its outermost covering (the dura).
Alternative Names
Subdural hemorrhage - chronic; Subdural hematoma - chronic
Causes, incidence, and risk factors
A subdural hematoma develops when tiny veins that run between the dura and the surface of the brain tear and leak blood. A collection of blood then forms over the surface of the brain. In a chronic subdural collection, the blood which leaks from the veins does so slowly over time. This can happen as a result of a head injury or, less frequently, it can occur spontaneously if the patient is elderly. Risks include head injury, old age, chronic use of aspirin or blood thinning (anti-coagulant) medication, and chronic heavy alcohol use.
Signs and tests
The physical exam will include a full neurologic work-up to test mental functions, strength, sensation, coordination, and walking/balance. If an abnormality is noted on the physical examination, a head CT or head MRI will be done to further evaluate the problem.
Treatment
The goal is to control symptoms and minimize or prevent permanent damage to the brain. Corticosteroid medications may be used to reduce swelling of the brain. Anticonvulsant medications such as phenytoin may be used to control or prevent seizures . Surgery may be required. This may include drilling a small hole in the skull to relieve pressure and allow blood to be drained. Large hematomas or solid blood clots may need to be removed through a larger opening in the skull ( craniotomy ).
Expectations (prognosis)
Chronic subdural hematomas will often heal themselves over time without requiring neurosurgery. If neurologic problems, seizures, or chronic headache are present, surgery may be needed. In most cases, patients do well with complete resolution of their symptoms over time. Some chronic subdural hematomas recur after surgery, however.
Calling your health care provider
Because of the risk of permanent brain damage, a health care provider should be called promptly if symptoms of chronic subdural hematoma appear.
Go to the emergency room or call the local emergency number (such as 911) if emergency symptoms develop, including convulsions / seizures , decreased responsiveness or loss of consciousness .
Prevention
Minimize the risk of head injury by using proper safety equipment (such as hard hats, bicycle or motorcycle helmets, and seat belts) when involved in activities that may result in brain injury .