Andrew Bivard

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BACKGROUND Intravenous alteplase is the only approved treatment for acute ischemic stroke. Tenecteplase, a genetically engineered mutant tissue plasminogen activator, is an alternative thrombolytic agent. METHODS In this phase 2B trial, we randomly assigned 75 patients to receive alteplase (0.9 mg per kilogram of body weight) or tenecteplase (0.1 mg per(More)
The use of perfusion imaging to guide selection of patients for stroke thrombolysis remains controversial because of lack of supportive phase three clinical trial evidence. We aimed to measure the outcomes for patients treated with intravenous recombinant tissue plasminogen activator (rtPA) at a comprehensive stroke care facility where perfusion computed(More)
PURPOSE To perform a large-scale systematic comparison of the accuracy of all commonly used perfusion computed tomography (CT) data postprocessing methods in the definition of infarct core and penumbra in acute stroke. MATERIALS AND METHODS The collection of data for this study was approved by the institutional ethics committee, and all patients gave(More)
Computed tomography perfusion imaging in acute stroke requires further validation. We aimed to establish the optimal computed tomography perfusion parameters defining the infarct core and critically hypoperfused tissue. Sub-6-h computed tomography perfusion and 24-h magnetic resonance imaging were analysed from 314 consecutive patients with ischaemic(More)
BACKGROUND Perfusion computed tomography (PCT) shows promise in acute stroke assessment. However, the accuracy of CT perfusion thresholds in defining the acute infarct core remains uncertain. METHOD Concurrent PCT and MRI-DWI performed 3-6 h after symptoms onset were assessed in 57 ischemic stroke patients. PCT was compared to DWI images to define the(More)
There is mounting evidence that shows how poorly non-contrast computed tomography (NCCT) Alberta Stroke Program Early CT Score (ASPECTS) performs in the first three-hours after stroke onset compared to Diffusion weighted (DWI) magnetic resonance imaging (MRI). It is time to move into the 21st century and use more advanced imaging routinely in hyper-acute(More)
Purpose To validate the use of perfusion computed tomography (CT) with whole-brain coverage to measure the ischemic penumbra and core and to compare its performance to that of limited-coverage perfusion CT. Materials and Methods Institutional ethics committee approval and informed consent were obtained. Patients (n = 296) who underwent 320-detector CT(More)
OBJECTIVE To compare the accuracy of Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and CT perfusion to detect established infarction in acute anterior circulation stroke. METHODS We performed an observational study in 59 acute anterior circulation ischemic stroke patients who underwent brain noncontrast CT, CT perfusion, and MRI within(More)
Whole-brain dynamic time-resolved computed tomography angiography (CTA) is a technique developed on the new 320-detector row CT scanner capable of generating time-resolved cerebral angiograms from skull base to vertex. Unlike a conventional cerebral angiogram, this technique visualizes pial arterial filling in all vascular territories, thereby providing(More)
BACKGROUND AND PURPOSE Magnetic resonance perfusion (MRP) and computed tomographic perfusion (CTP) are being increasingly applied in acute stroke trials and clinical practice, yet the comparability of their perfusion values is not well validated. The aim of this study was to validate the comparability of CTP and MRP measures. METHODS A 3-step approach was(More)