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Acute Stroke Imaging Part I: Fundamentals

Published online by Cambridge University Press:  02 December 2014

K. Butcher*
Affiliation:
Division of Neurology, University of Alberta, Edmonton, Alberta, Canada
D. Emery
Affiliation:
Department of Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada
*
Division of Neurology, 2E3 WMC Health Sciences Centre, University of Alberta, 8440 112th St., Edmonton, Alberta, T6G 2B7, Canada.
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Abstract

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Neuroimaging is essential to stroke diagnosis and management. To date, the non-contrast CT has served as our main diagnostic tool. Although brain parenchymal changes visible on CT do provide valuable prognostic information, they provide limited insight into the potential for tissue salvage in response to reperfusion therapy, such as thrombolysis. Newer advanced CT and MRI based imaging techniques have increased the detection sensitivity for hyperacute and chronic parenchymal changes, including ischemia and hemorrhage, permit visualization of blood vessels and cerebral blood flow. This review outlines the basic principles underlying acquisition and interpretation of these newer imaging modalities in the setting of acute stroke. The utility of advanced brain parenchymal and blood flow imaging in the context of acute stroke patient management is also discussed. Part II in this series is a discussion of how these techniques can be used to rationally select appropriate patients for thrombolysis based on pathophysiological data.

Résumé:

RÉSUMÉ:

La neuroimagerie est essentielle au diagnostic et à la prise en charge de l’accident vasculaire cérébral. À ce jour, la tomodensitométrie sans contraste constitue le principal outil diagnostique. Bien que les changements du parenchyme cérébral visibles à la tomodensitométrie fournissent une information précieuse sur le pronostic, ils offrent peu d’informations sur la possibilité de préserver des tissus potentiellement viables en réponse aux traitements de reperfusion comme la thrombolyse. L’imagerie basée sur les techniques nouvelles plus avancées de tomodensitométrie et de résonance magnétique ont augmenté la sensibilité de détection des changements parenchymateux hyperaigus et chroniques, dont l’ischémie et l’hémorragie, et permettent la visualisation des vaisseaux sanguins et du flot sanguin cérébral. Cette revue décrit les principes de base sous–jacents à l’acquisition et à l’interprétation de ces nouvelles modalités d’imagerie dans le contexte de l’accident vasculaire cérébral aigu. L’utilité de l’imagerie spécialisée du parenchyme et du flot sanguin cérébral dans le contexte de la prise en charge de l’accident vasculaire cérébral est également abordée. La deuxième partie de cette série discute de l’utilisation de ces techniques pour sélectionner de façon appropriée les patients pour la thrombolyse en se basant sur des données physiopathologiques.

Type
Review Article
Copyright
Copyright © The Canadian Journal of Neurological 2010

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