Motor vehicle accidents and falls often result in head injuries due to the force or impact that causes the brain to crash into the skull. Less commonly, an external object or a piece of skull enters the brain tissue. Both types of trauma often cause bleeding inside the skull, as well as the damage to the tissues.
According to the Cleveland Clinic, about 25% of head injuries result in a subdural hematoma.
What is a subdural hematoma?
Within the skull, there are three meninges, which are membrane layers. These provide a covering for the brain and protect it. A head trauma may cause a vein or other blood vessel to tear and begin leaking into the layer below the dura (hence, subdural). Doctors may refer to the hematoma as a subdural hemorrhage or an intracranial hematoma, and it is a type of traumatic brain injury.
Why is a subdural hematoma dangerous?
If the hematoma is acute, the symptoms show up right away. The blood is pooling quickly and causing serious pressure against the brain, leading to permanent brain damage, paralysis or death. Immediate diagnosis and treatment may be the only way to save a person’s life.
Subacute and chronic subdural hematomas involve much slower blood vessel leaks. One of the dangers to this is that the pool of blood grows very slowly, and the pressure increases gradually; a person may not develop symptoms for weeks or even months after the trauma. Even a minor concussion could cause a small rip in a blood vessel, so any trauma may have the potential to cause permanent brain damage.
What are the symptoms of subdural hematomas?
Most of the initial symptoms are common to any type of TBI. A person may experience one or more of the following:
- Blurred vision and other sensory changes
- Muscle weakness
- Loss of focus or other cognitive functions
- Memory loss
As the pressure builds, a person may develop seizures or breathing problems, become paralyzed or lose consciousness and enter a coma. If the pressure builds slowly, there is a danger that the person will not connect the symptoms to the accident, and a doctor may not recognize the issue until the damage is permanent.