Abstract W MP13: Stroke Thrombolysis: Comparing CTA, CTP and NCCT Imaging Criteria for Thrombolysis

Abstract

Background: We examined the important and controversial issue of the value of various advanced imaging methods in a large, prospective cohort of acute stroke patients at a university hospital stroke centre that routinely uses multimodal CT imaging to assist thrombolytic treatment decisions. Methods: We prospectively collected baseline, 24 hour, and day 90 clinical and imaging data from acute ischemic stroke patients being assessed for acute thrombolytic therapy at a centre where multimodal CT (NCCT, perfusion CT, and CT angiography) is used routinely as part of the decision-making process for thrombolysis. NCCT was assessed with the ASPECTS scoring system, CTA was graded for collateral flow and occlusion status and on CTP patients were classified according to the DEFUSE2 ‘target mismatch’ criteria. Patients treated with thrombolysis were compared to those who were untreated to generate odd ratios for mRS 0-1 and 5-6 and regression statistics were used to compare the imaging profiles to mRS. Results: 368 rtPA treated patients with hemispheric ischaemic stroke and complete follow-up were analysed. Treated patients ASPECTS >7 had mRS 0-1 OR 0.6 compared to untreated, and mRS 5-6 OR 1.98. Patients Treated patients with an ASPECTS score <7 had mRS 0-1 OR 0.18, mRS 5-6 OR 3.30, with an ASPECTS score >7 and occlusion on CTA had mRS 0-1 OR 2, mRS 5-6 OR 0.76. Patients with an ASPECTS score >7 and occlusion and good distal collateral flow on CTA had mRS 0-1 OR 2.91, mRS 5-6 OR 0.94. Patients with CTP DEFUSE2 mismatch had mRS 0-1 OR 11.93, mRS 5-6 OR 0.52. Patients with CTP DEFUSE2 mismatch and occlusion on CTA mRS 0-1 OR 19.71, mRS 5-6 OR 0.36. Conclusions: Acute CTP selection criteria was the strongest predictor of outcome compared to either NCCT ASPECTS or combined NCCT and CTA criteria.