Brain Imaging Findings and Response to Intravenous Thrombolysis in Posterior Circulation Stroke

Introduction Intravenous thrombolysis (IVT) is a standard treatment for both anterior circulation ischaemic stroke (ACIS) and posterior circulation ischaemic stroke (PCIS). Our aim was to evaluate the predictors for a good clinical outcome and intracerebral haemorrhage (ICH) in patients undergoing posterior circulation IVT based on the initially performed CT or MR imaging. Methods The study cohort consisted of 1643 consecutive patients with acute ischaemic stroke (1440 ACIS, 203 PCIS cases) who underwent IVT. ICH was classified according to the European Cooperative Acute Stroke Study (ECASS) I protocol. Clinical outcome was assessed using the modified Rankin scale (mRS). Early ischaemic signs and pre-existing structural signs were assessed. Results Good clinical outcomes (mRS 0–1) were noted in 45.3% of patients with PCIS, with a mortality rate of 14.8%. ICH was noted in 8.3%, and a large haemorrhage was found in 2.4% of patients. Some early ischaemic signs and pre-existing structural signs on initial CT/MR imaging correlated significantly with the 90-day clinical outcome. Conclusions Early ischaemic signs and pre-existing structural signs should be considered during the assessment of patients with PCIS eligible for IVT. Tissue hypoattenuation on initial CT scans correlates with an increased risk of death. Similarly to anterior circulation, atrophy on initial MRI may negatively predict good clinical outcome in posterior circulation.