Computed Tomography Perfusion Alberta Stroke Program Early Computed Tomography Score Is Associated with Hemorrhagic Transformation after Acute Cardioembolic Stroke.

Alberta Stroke Program Early Computed Tomography (CT) score (ASPECTS) has been applied to CT perfusion (CTP) with good interrater agreement to predict early ischemic stroke, and it can be useful in decision making in acute ischemic stroke. The aim of the present study was to assess the predictive value of CTP ASPECTS of hemorrhagic transformation (HT) in acute cardioembolic stroke. This is a single-enter, retrospective study. All patients hospitalized with acute cardioembolic stroke from January 2008 to September 2013 were included. ASPECTS of baseline non-contrast CT, CTP maps of cerebral blood volume (CBV), cerebral blood flow, and mean transit time were collected from 52 consecutive patients with less than 12-h anterior circulation ischemic stroke. MRI scan was performed within 72 h of symptom onset after index stroke including T2*-weighted gradient echo to identify HT. For bleeding risk assessment, CTP and diffusion-weighted imaging ASPECTS were categorized into 0-7 or 8-10. Baseline characteristics, ASPCETS scores and HT were compared. Eighteen (34.6%) patients had HT and four (7.7%) developed symptomatic HT. On univariate analysis, the proportion of patients with CBV-ASPECTS 0-7 was significantly higher in HT patients as compared to patients without HT (44 versus 9%, P = 0.005). CBV ASPECTS 0-7 remained independent prognostic factors for HT after adjustment for clinical baseline variables. CBV ASPECTS could be of value to predict HT risk after acute cardioembolic stroke and may be a quick risk assessment approach before reperfusion therapy.

Intracranial Posterior Circulation Large Artery Thrombi Visualized Using Susceptibility-Weighted MRI.

PURPOSE: To identify thrombi in patients with posterior circulation large artery occlusion using susceptibility-weighted magnetic resonance imaging (MRI). METHODS: All patients hospitalized with intracranial posterior circulation occlusion from January 2003 to September 2013 were included. MRI and computed tomography angiography were reviewed to determine the presence of arterial occlusion and identify thrombi. Eighty-one patients were analyzed to investigate susceptibility vessel sign (SVS) that was identified as blooming artifact (BA) on T2*-weighted gradient echo imaging. RESULTS: We identified 21 of 63 (33.3%) patients with BA in symptomatic patients, and 1 of 18 (5.6%) in the asymptomatic group with significant difference (P = .019). BAs were found in 6 of 10 (60.0%) patients with cardioembolism, 5 of 13 (38.5%) with dissection, 9 of 34 (26.5%) with large artery atherosclerotic disease, and 1 of 6 (16.7%) with undetermined cause. CONCLUSION: Identifying SVS may be useful in exploring the fresh thrombi and the mechanism of posterior circulation stroke.

Thrombolysis in ischemic stroke without arterial occlusion at presentation.

BACKGROUND AND PURPOSE: None of the randomized trials of intravenous tissue-type plasminogen activator reported vascular imaging acquired before thrombolysis. Efficacy of tissue-type plasminogen activator in stroke without arterial occlusion on vascular imaging remains unknown and speculative. METHODS: We performed a retrospective, multicenter study to collect data of patients who presented to participating centers during a 5-year period with ischemic stroke diagnosed by clinical examination and MRI and with imaging evidence of no vascular occlusion. These patients were divided into 2 groups: those who received thrombolytic therapy and those who did not. Primary outcome measure of the study was excellent clinical outcome defined as modified Rankin Scale of 0 to 1 at 90 days from stroke onset. Secondary outcome measures were good clinical outcome (modified Rankin Scale, 0-2) and perfect outcome (modified Rankin Scale, 0). Safety outcome measures were incidence of symptomatic intracerebral hemorrhage and poor outcome (modified Rankin Scale, 4-6). RESULTS: A total of 256 patients met study criteria, 103 with thrombolysis and 153 without. Logistic regression analysis showed that patients who received thrombolysis had more frequent excellent outcomes with odds ratio of 3.79 (P<0.01). Symptomatic intracerebral hemorrhage was more frequent in thrombolysis group (4.9 versus 0.7%; P=0.04). Thrombolysis led to more frequent excellent outcome in nonlacunar group with odds ratio 4.90 (P<0.01) and more frequent perfect outcome in lacunar group with odds ratio 8.25 (P<0.01). CONCLUSIONS: This study provides crucial data that patients with ischemic stroke who do not have visible arterial occlusion at presentation may benefit from thrombolysis.