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Acute Stroke Imaging Part II: The Ischemic Penumbra

  • K. Butcher (a1) and D. Emery (a2)


In acute ischemic stroke, the volume of threatened but potentially salvageable tissue, i.e. the ischemic penumbra, is critical to the success of all acute therapeutic interventions, most notably thrombolysis. Despite the availability of both CT and MRI based techniques to detect and assess the penumbra, advanced imaging of this type remains under-utilized. Although the optimal selection criteria are still being refined and technical improvements are ongoing, rapid imaging of the penumbra appears to be the most promising approach to expanding the acute thrombolysis population, as well as tailoring treatment based on specific pathophysiological findings. This second article in a two-part series reviews current evidence for penumbral-based treatment selection and discusses the barriers to implementation of these advanced imaging techniques in acute stroke management protocols.


Enphase aigue de l’accident vasculaire cerebral, le volume du tissu a risque mais potentiellement viable, c’est–a–dire la penombre ischemique, est tres important pour le succes de toute intervention therapeutique dont la thrombolyse. Malgre la disponibilite de techniques basees sur la tomodensitometrie et sur l’imagerie par resonance magnetique pour detecter et evaluer la penombre, ces types d’imageries demeurent sous–utilisees. Bien que les criteres de selection optimaux ne soient pas encore bien definis et que la technologie se perfectionne continuellement, l’approche la plus prometteuse pour augmenter la population de patients qui subissent une thrombolyse en phase aigue ainsi que pour individualiser le traitement sur la base de constatations physiopathologiques specifiques demeure l’imagerie rapide de la penombre. Ce second article de cette serie de deux articles revoit les donnees actuelles concernant le choix du traitement base sur la penombre et discute des barrieres a l’utilisation de ces techniques avancees d’imagerie dans les protocoles de prise en charge de l’accident vasculaire cerebral aigu.

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Corresponding author

Division of Neurology, 2E3 WMC Health Sciences Centre, University of Alberta, 8440 112th St., Edmonton, Alberta, T6G 2B7, Canada.


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Acute Stroke Imaging Part II: The Ischemic Penumbra

  • K. Butcher (a1) and D. Emery (a2)


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