Posterior circulation infarction (POCI)

Case contribution: Dr Radhiana Hassan


  • A 57 years old with underlying hypertension and diabetes mellitus
  • He presented with presyncopal attack, giddiness and vomiting
  • Later on had loss of consciousness
  • No fitting episode and no fever
  • Urgent CT scan brain was normal
  • Initially treated as acute myocardial infarction
  • However his condition deteriorated and a repeat CT scan brain was performed.
Initial urgent CT brain shows normal finding


Subsequent CT scan brain in axial plane soft tissue window done 2 days after first CT scan

CT scan findings:

  • Acute communicating hydrocephalus with effacement of cerebral sulci
  • Extensive hypodensities seen in the brain stem, both thalami, temporal and occipital lobe
  • Involvement is symmetrical on both sides
  • These findings are not seen on previous scan
  • No intracranial hemorrhage

Diagnosis: Posterior circulation infarction (POCI)


  • Posterior circulation infarctions represent about 20% of all ischaemic stroke
  • A posterior circulation infarction is classically defined by infarction occuring within the vascular territory by the vertebrobasilar arterial system
  • Atheroscleotic disease can result in thromboembolism leading to ischaemia. Large vessel atherosclerotic changes occur in about 35% of POCI and small vessel disease in 13%.  Other causes include cardioembolism, arterial dissection, vertebrobasilar dolichoectasia, subclavian steal syndrome, giant cell arteritis and Fabry disease.
  • Imaging shows areas correspond to vertebrobasilar vascular territory that includes
    • Brain stem
    • Cerebellum
    • Midbrain
    • Thalami
    • Temporal and occipital lobe
Author: radhianahassan