Extradural Haemorrhage

Question 1

What is an extradural haemorrhage?

Answer 1

An Extradural haematoma (EDH) is a pathological condition where blood collects between the dura mater, the outermost meningeal layer, and the inner surface of the skull. This condition is commonly arterial in origin, with the middle meningeal artery often implicated.

Question 2

Describe the aetiology of extradural haemorrhages

Answer 2

TRAUMA:
- Usually due to fracture of the temporal or parietal bones leading to rupture of the middle meningeal artery and vein – typically after trauma to temple just lateral to eye (the PTERION region)
- >95% of extradural haemaotomas are supratentorial
- Can also be due to tear in a dural venous sinus

Question 3

What are the risk factors for an extradural haemorrhage?

Answer 3

Bleeding tendency
E.g. haemophilia, anticoagulant therapy

Question 4

Summarise the epidemiology of extradural haemorrhage

Answer 4

UK incidence: 20/10,000
10% of severe head injuries
Most commonly seen in YOUNG ADULTS

Question 5

What are the presenting symptoms of extradural haemorrhage

Answer 5

• Head injury with temporary loss of consciousness/drowsiness
• Followed by lucid interval – resolved consciousness levels
• Followed by progressive deterioration in conscious level (GCS) – as ICP rises
• Increasingly severe headache, vomiting, confusion and fits follow +/- hemiparesis (one-sided muscle weakness) with brisk reflexes and upgoing plantar.
• If bleeding continues, ipsilateral pupil dilates, coma deepens, bilateral limb weakness develops and breathing becomes deep and irregular (brainstem compression)

Question 6

What are the signs of an extradural haemorrhage that can be found on physical examination?

Answer 6

1. Scalp trauma or fracture
   Headache
2. Deteriorating GCS
3. Signs of raised ICP
   - E.g. dilated, unresponsive pupil on the side of the injury
4. Cushing’s Reflex
   - Hypertension
   - Bradycardia
   - Irregular breathing

Question 7

What investigations are used to diagnose/ monitor an extradural haemorrhage?

Answer 7

Urgent CT Scan:
- Check for a haematoma – may also get a contracoup injury on opposite side – due to acceleration-deceleration forces during injury
- The typical finding is a lentiform or biconvex hyperdense extra-axial collection, most often unilateral and supratentorial.
- Look for features of raised ICP (e.g. midline shift)
- Secondary features such as midline shift or subfalcine/uncal herniation should be assessed as they may necessitate urgent neurosurgical intervention.

Question 8

How are extradural haemorrhages managed?

Answer 8

Management of EDH depends on the severity of the symptoms and the extent of the mass effect on the brain, which is often assessed through imaging studies. It can range from conservative management with close observation in mild cases to urgent neurosurgical evacuation of the haematoma in severe cases.