Extradural (Epidural) Hematoma (EDH)
Forensic Pathology: Traumatic Head Injury
1. Mechanism & Presentation
An EDH is a collection of blood between the skull and the dura mater. It is classically associated with injury to the middle meningeal artery (usually resulting from a fracture of the temporal bone).
- The “Lucid Interval”: A hallmark clinical feature where the patient suffers an initial loss of consciousness, recovers, and subsequently experiences rapid neurological deterioration as the hematoma expands.
- Shape: Typically biconvex or lens-shaped on imaging (CT/MRI), as the blood is contained by the tight adherence of the dura to the skull sutures.
2. Forensic Pearls
| Key Forensic Feature | Clinical Context |
|---|---|
| Fracture Association | Rarely occurs without an underlying skull fracture (usually temporal/parietal). |
| Vital Reaction | The hematoma is usually adherent to the skull and shows evidence of clotting (indicating it was formed while the heart was beating). |
| Heat Hematoma | Crucial Differential: Must be distinguished from a “heat hematoma” found in burned bodies, which is chocolate-colored, friable, and not associated with skull fractures. |
3. Medico-Legal Significance
- Cause of Death: Usually due to increased intracranial pressure (ICP), leading to brain herniation (uncal or tonsillar).
- Documentation: During autopsy, the presence of skull fractures and the site of arterial rupture must be carefully photographed and described, as this is often central to establishing the mechanism of injury in criminal investigations.