Blood-brain barrier permeability assessed by perfusion computed tomography predicts hemorrhagic transformation in acute reperfusion therapy

Hemorrhagic transformation (HT) is one of the most feared complications of acute recanalization therapies. The aim of this study was to evaluate whether blood-brain barrier permeability (BBBP) imaging can predict HT in the setting of acute recanalization therapy and to determine the sensitivity and specificity of BBBP for the prediction of HT according to the type of reperfusion therapy. We assessed a total of 46 patients who received recanalization therapy (intravenous (IV) recombinant tissue plasminogen activator (tPA), mechanical thrombectomy with a stent retriever or both) for acute ischemic stroke within the internal carotid artery or middle cerebral artery. BBBP above the threshold was significantly associated with HT after adjustment for confounding factors in all patients (OR 45.4, 95% CI 2.9~711.2, p = 0.007), patients who received IV tPA (OR 20.1, 95% CI 1.2–336.7, p = 0.037), and patients who received endovascular therapy (OR 47.2, 95% CI 1.9–1252.5, p = 0.022). The sensitivity and specificity of the initial BBBP measurement as a predictor of HT in the overall 46 patients were 80 and 71%, respectively. These values were 75 and 64% in only IV tPA group, 100 and 80% in only endovascular group, 77 and 67% in IV tPA with or without endovascular therapy group, and 86 and 76% in endovascular therapy with or without bridging IV tPA therapy group. Increased pretreatment BBBP values were significantly associated with HT after acute recanalization therapy. This correlation with HT was stronger in patients receiving endovascular mechanical thrombectomy than in patients receiving IV rtPA.