What is the relationship among penumbra volume, collaterals, and time since onset in the first 6 h after acute ischemic stroke?

Cheripelli, B. K., Huang, X., McVerry, F. and Muir, K. (2016) What is the relationship among penumbra volume, collaterals, and time since onset in the first 6 h after acute ischemic stroke? International Journal of Stroke, 11(3), pp. 338-346. (doi: 10.1177/1747493015620807) (PMID:26763919)

Abstract

Background: The steep, time-dependent loss of benefit from reperfusion in clinical trials is consistent with loss of penumbra over the early hours of ischemia, as observed in animal models. Human imaging studies, however, show persistent penumbra for up to 48 h. We investigated core and penumbra volumes and collateral status in relation to time after stroke onset within the first 6 h. Methods: Using data from three multimodal computer tomography-based studies in acute ischemic stroke patients <6 h after onset, we measured core and penumbra volumes, collateral status, and target mismatch (defined as core volume < 50 ml, perfusion lesion volume > 15 ml, mismatch ratio > 1.8). Patients were grouped by onset to imaging time (<3, 3–4.5, 4.5–6 h). We explored correlates of penumbra proportion by multivariable linear regression. Results: Analysis included 144 subjects. Across time epochs, neither proportions of penumbra (59%, 64%, 75% at <3, 3–4.5, >4. 5 h, respectively, p = 0.4) nor poor collaterals (15/56 (27%), 14/47 (30%), 4/15 (27%) at <3, 3–4.5, >4.5 h, p = 0.9) differed significantly. Penumbra proportion was not clearly related to time to imaging (R2 = 0.003; p = 0.5) but a trend for divergent effects by collateral status was seen (slight increase in penumbra over time with good collaterals versus reduced with poor, interaction = 0.08). The proportion of patients with target mismatch did not vary by time (56%, 74%, and 67% at <3, 3–4.5, >4.5 h, p = 0.09). Conclusions: In a cross-sectional sample imaged within 6 h, neither the proportions of penumbral tissue nor “target mismatch” varied by time from onset. A trend for reducing penumbra proportion only among those with poor collaterals may have pathophysiological and therapeutic importance.

• Item Type: Articles
• Additional Information: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: ATTEST, POSH studies were funded by The Stroke Association; MASIS was supported by Translational Medicine Research Collaboration (a consortium comprising the Universities of Aberdeen, Dundee, Edinburgh and Glasgow, the four associated NHS Health Boards (Grampian, Tayside, Lothian and Greater Glasgow and Clyde).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Cheripelli, Dr Bharath Kumar and Huang, Dr Xuya and Muir, Professor Keith and McVerry, Dr Ferghal
• Authors: Cheripelli, B. K., Huang, X., McVerry, F., and Muir, K.
• College/School: College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience
• Journal Name: International Journal of Stroke
• Journal Abbr.: Int J Stroke
• Publisher: SAGE Publications
• ISSN: 1747-4930
• ISSN (Online): 1747-4949
• Published Online: 05 January 2016
• Copyright Holders: Copyright © 2016 World Stroke Organization
• First Published: First published in International Journal of Stroke 11(3): 338-346
• Publisher Policy: Reproduced in accordance with the publisher copyright policy