Pathogenesis (disease development)
The brain is enveloped by three densely packed meninges (meninges; layers of connective tissue). They protect and stabilize the brain. The dura mater is the outermost and thickest layer. It is directly adjacent to the skull. The middle meninges are called arachnoid mater (cobweb skin). The pia mater (delicate meninges) is the innermost meninges and lies directly on top of the brain. The two inner layers are also called or combined as the soft meninges. Between the meninges run blood vessels and is the cerebrospinal fluid (CSF).
The epidural hemorrhage is localized between the cranial bone and the dura mater. The origin of the hemorrhage in most cases (85%) is a rupture (tear) of the meningeal artery (supplies the meninges). The media meningeal artery is located under the temporal bone and is frequently involved in a skull fracture. Similarly, lesions of the duravena or sagittal/transverse sinus can cause epidural hematoma (15% of cases). In this case, symptoms develop more slowly because ruptured veins bleed less than injured arteries.
Etiology (Causes)
Nontraumatic epidural hematoma.
Behavioral causes
- Consumption of stimulants
- Alcohol abuse (alcohol dependence)
Diseases
- Hypertension (high blood pressure) – promotes the development of epidural hematoma due to vasodamaging effects.
- Intracranial metastases
- Coagulopathies (blood clotting disorders).
- Sickle cell anemia (sickle cell disease).
- Sinusitis sphenoidalis (sphenoid sinusitis).
- Sinus vein thrombosis (SVT)
- Vascular malformations (congenital malformations of the vascular system).
Medications
- Anticoagulants (anticoagulants).
Acute traumatic epidural hematoma
- Traumatic brain injury (TBI) with fracture of the pterion of the cranial dome (site on the skull near the sphenoparietal sutura) due to a fall, blow to the head, or in the context of a traffic accident