27. Imaging in neurotrauma.
- Modalities
- Non-contrast CT head
- Trauma
- Suspected intracranial haemorrhage
- For example “worst headache of my life”
- (Not in tension headache)
- MRI head
- Pre-operative work up
- Non-contrast CT head
- Haemorrhage on non-contrast CT
- Acute – hyperdense
- Subacute – isodense with brain
- Late/chronic – hypodense
- Epidural haematoma
- Arterial origin
- Mostly middle meningeal arterty
- Findings
- Biconvex hyperdense lesion
- Sharply demarcated
- Doesn’t displacement meninges
- Is limited by suture lines
- Can cross falx and tentorium
- Has mass effect
- Arterial origin
- Subdural haemoatoma
- Venous origin
- Mostly bridging veins
- Findings
- Crescent shaped hyperdense lesion
- Falx cerebri displaced
- Bleeding can be parafalcine
- Is between dura and arachnoid
- Not limited by suture lines (can cross them)
- Has mass effect (can cause midlift shift due to displacement)
- The intensity of the lesion changes with time from hyperdense to isodense to hypodense
- Clinical features
- “Worst headache of my life”/thunderclap headache
- Altered mental status
- Photophobia
- Nuchal rigidity
- Vomiting
- Venous origin