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Collaterals and Elusive Ischemic Penumbra

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Abstract

As alternative blood supply routes, collateral blood vessels can play a crucial role in determining patient outcomes in acute and chronic intracranial occlusive diseases. Studies have shown that increased collateral circulation can improve functional outcomes and reduce mortality, particularly in those who are not eligible for reperfusion therapy. This article aims to discuss the anatomy and physiology of collateral circulation, describe current imaging tools used to measure collateral circulation, and identify the factors that influence collateral status.

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  1. Neurology Department, UCLA Health, Los Angeles, CA, USA

    Smit D. Patel & David Liebeskind

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Highlights

• Anatomy of the brain’s collateral circulation.

• Vascular biology of the brain’s collateral circulation.

• Measurement of collateral flow and the ischemic penumbra.

• Clinical and imaging definitions of collateral status.

• Impact of collateral flow on evolution of the penumbra and penumbral salvage after stroke.

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Patel, S.D., Liebeskind, D. Collaterals and Elusive Ischemic Penumbra. Transl. Stroke Res. 14, 3–12 (2023). https://doi.org/10.1007/s12975-022-01116-2

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