Accumulation of blood in the subdural space following rupture of a vein

Aetiology

• Typically occur in elderly individuals, particularly those over 65 years of age
• Often a consequence of minor trauma, leading to shearing forces that tear bridging veins between the cortex and dura mater

Risk factors

• Advancing age (>65 years old)
• Bleeding disorders or anticoagulant therapy
• Chronic alcohol use
• Recent trauma

Clinical features

Clinical presentation of a subdural haematoma varies but may include:

• Headache
• Nausea or vomiting
• Confusion
• Diminished eye, verbal, or motor response
• Focal neurological signs indicating the haematoma site
  • Epilepsy occasionally occurs
  • Stupor, coma and coning may follow

The presentation is typically sub-acute (within 3 days to 3 weeks) or chronic (>3 weeks)

Investigations

• Urgent CT brain: classically shows a crescent of blood around the brain tissue, and midline shift
  • Follows the contour of the skull as it is not restricted by skull sutures
• If absent, and still suspicious, do lumbar puncture to confirm - will be blood in CSF