CT scan in the investigation of stroke
Last reviewed 01/2018
CT's are attractive on account of their simplicity to perform, rapidity, largely non-invasive nature, low cost and ability to distinguish ischaemia and haemorrhage.
Disadvantages in the assessment of ischaemic stroke:
- the full extent of infarcted tissue cannot be defined until several days afterwards
- CT scans are best done promptly, preferably within 48 hrs of, and no later than 7 days after, the onset of symptoms (1)
- there may be a period of isodensity at day 3
- repeat scans are essential to determine prognosis
- visualisation may be assisted using contrast media but at the increased complexity and risk
- the brainstem structures are poorly displayed because of bony artifacts
Disadvantage in the assessment of haemorrhage:
- difficult to distinguish primary cerebral haemorrhage from confluent haemorrhagic infarction
Reference:
- 1. Drug and Therapeutics Bulletin 1998; 36 (7): 51-6.
CT appearance of subdural haemorrhage