Arterial dissection


  • If the inner lining (intima) of an artery tears, spontaneously or due to trauma), blood can travel into the wall of the artery. This dissection can block the artery or be a source of embolism (see image below).
  • Dissection can affect the aorta, carotid or vertebral arteries
  • Dissection of the aorta or vertebrals can lead to massive haemorrhage into the chest or subarachnoid space respectively
  • Bleeding is very unusual after carotid dissection

Section of corotid artery showing embolism

Image labels:

Section 1

Carotid Artery:

  • Common carotid artery
  • “Intima” i.e. arterial lining
  • Internal carotid artery
  • External carotid artery

Section 2

  • blood clot in the wall of the artery causing narrowing
  • Tear in intima raising a flap

Section 3

  • narrowing may worsen to completely block artery
  • clot may form on tear and then embolise to brain.