Epidural hematoma is a life-threatening complication of head injuries. To understand the issue, it is necessary to know some information about the intracranial (skull) anatomy.
In the intracranial cavity there is the brain covered with three meninges. The layer located nearest to the brain is known as pia mater, the middle meninx is called arachnoidea and the meninx right under the skull is called dura mater. The term epidural hematoma ("epi" is a Latin expression for "above") means presence of blood in the space "above" the dura mater, i.e. between the dura mater and the skull bone.
The bleeding into the epidural space is caused by a damage of artery known as the middle meningeal artery (arteria meningea media), which is located in the temple area on both sides of the skull. Head injury, especially in this location, can lead to a rupture of this artery and subsequent bleeding. The space between the dura mater and cranial bone starts to fill with blood and the developing and growing hematoma slowly compresses the brain. Arterial bleeding is in general more massive and dangerous than venous bleeding and this is not an exception – bleeding from the middle meningeal artery never stops itself and it is fatal without proper medical care.
Injury that is accompanied with the rupture of middle meningeal artery may manifest with symptoms that are expectable by a “non-complicated” head trauma such as short period of unconsciousness, dizziness, headache, vomiting, etc. In classic course of epidural hematoma formation, the affected person returns more or less to a normal condition. However, this is only temporary and illusory improvement as the artery bleeds and the hematoma gradually grows. There is only limited space in the skull; the hematoma causes intracranial hypertension and brain compression. This is accompanied by a progressive loss of consciousness and eventually leads to death within a few hours after the injury.
In a person after a head injury, it is important to watch the pupils. Epidural hematoma often compresses the nerve responsible for the width of the pupil. Therefore, the first sign of growing epidural hematoma may be a sudden unilateral dilation of the patient’s pupil on the side of injury.
Every more powerful head injury should lead to an examination, in ideal case by a neurologist. The hematoma can be visualized by using an imaging method such as computed tomography or magnetic resonance imaging. The hematoma looks like a lentil-shaped lesion located just under the skull bone.
Diagram - Epidural hematoma
People should avoid direct blows to the head and especially protect the temple area. Head injuries should not be underestimated and the injured should seek medical assistance.
The treatment should be as quick as possible. Epidural hematoma must be solved by a neurosurgical intervention. The procedure aims to create a skull opening and drain the accumulated blood to protect the brain. When this is done, the surgeon stops the bleeding.