Background
Epidemiology
- Occurs in 5% of closed head injuries
- But up to 27% of severe head injuries
Pathophysiology
- Rupture of bridging veins traversing subdural space
- Acceleration contributes but not impact
- Can occur without apparent trauma in the elderly or due to anticoagulation and a minor injury
- Often shows underlying parenchymal damage
- Chronic subdural bleeds are common in the elderly or in patients with shunts (related to over-draining)
Clinical Manifestations
- Acute
- May be minor trauma that patient doesn't even remember
- More common with falls than motor vehicle collisions
- Chronic
- Elderly patients
- Patients with shunts that are over-draining
Investigations
- CT head shows crescent-shaped bleed
- Midline shift >1 cm is very worrying and requires urgent neurosurgery
