Dynamic Contrast-enhanced Ultrasound Imaging for Cerebral Perfusion Measurement in Acute Ischemic Stroke

Stroke, a personal, familial, and social disaster, is the first cause of acquired disability, the second cause of dementia, and the third cause of death worldwide. Its associated socio-economic costs are astronomic. The burden of stroke is likely to increase, given the aging of the population and the growing incidence of many vascular risk factors. Therefore, apart from further development of stroke prevention and treatment strategies, rational and effective tools for diagnosis, monitoring, and follow-up for stroke patients have potential high long-term clinical and economic consequences. For neuroradiological work-up, computed tomography (CT) or magnetic resonance imaging (MRI) are used as gold standard techniques to detect presence or absence, effective state, and extent of stroke. However, these techniques achieve simply a baseline study of ischemia occurred and can deliver only a snapshot of brain parenchyma and vessels. Furthermore, their rapid and actual availability, especially in primary hospitals, and their dynamic capabilities and predictive values for further infarction are poor with critically ill patients have to be repeatedly transferred to the scanning unit for each measurement. Whereas CT examination is associated with x-ray radiation and may miss early detection of stroke, MRI is associated with higher costs and not generally routinely and around-the clock available in all the hospitals. Therefore, a simple, fast, repeatable, non-hazardous, and non-invasive dynamic bedside tool for the detection of acute brain tissue hypoperfusion and monitoring for potential further infarction or efficacy of thrombolysis either by systemic intravenous thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA) or by selective intraarterial fibrinolysis and mechanical recanalization, both combined with or without bridging after acute ischemic stroke, is strongly needed. A promising alternative method of diagnosing stroke represents contrast-enhanced