A subdural hematoma occurs when blood vessels between the brain and its outermost membrane rupture, causing leaking blood that results in compression of the brain tissue. Subdural hemotomas are classified as acute, characterized by immediate signs and symptoms; subacute, characterized by symptoms that appear within several hours; and chronic, characterized by signs and symptoms take days or even months to appear.
What is a Subdural Hematoma?
In a subdural hematoma, bleeding occurs between the dura (the outermost level of the brain) and the next layer, which is called the arachnoid. Blood collects between these layers of tissue that surround the brain and create pressure, which can lead to symptoms of subdural hematoma. Severe pressure may lead to unconcsciousness or death if not properly diagnosed or treated.
Causes of Subdural Hematoma
Serious head injuries can lead to subdural hematoma. However, even minor head injuries, especially in the elderly, can lead to chronic subdural hematomas. There are factors that increase risk for subdural hematoma, although some occur spontaneously.
- Repeated head injury
- Very young or very old age
- Anticoagulant medication such as blood thinners
- Recurrent falls
- Long-term abuse of alcohol
- Complication of a spinal tap (rare)
Symptoms of Subdural Hematoma
Signs of subdural hematoma include:
- Impaired cognitive function
- Dilated pupils
- Speech issues
- Weakness in limbs on one side of the body
If the condition goes undiagnosed and more blood causes additional brain tissue compression, more severe signs and symptoms include:
Treatment for Subdural Hematoma
Treatment for hematoma often includes surgery, depending on the severtity. In some cases, very small subdural hematomas that don’t produce signs or symptoms don’t have to be removed. Doctors may opt to simply observe the subdural hematoma with repeated head imaging tests. Medications designed to reduce and control swelling in the brain are also used, such as diuretics and corticosteroids.
If the subdural hematoma is severe and life-threatening, emergency surgery may be needed. Doctors may perform a craniotomy, which creates a large opening in the skull to drain blood and relieve pressure on the brain. Alternatively, the doctor may perform a craniectomy in which a section of the skull is removed for an extended period of time to allow the injured brain to expand and swell without permanent damage. This form of treatment is not often used to treat sudural hematoma.
Prognosis for Subdural Hematoma
Degree and rate of recovery varies from patient to patient, depending upon the severity of the subdural hematoma, as well as how quickly it was discovered and treated. As a general rule of thumb, adults experience most of their recovery within six months, while children recover more quickly and more completely. Seizure, which can most often be controlled with medication, is a common long-term complication.