Perfluorocarbons Enhance a T2*-Based MRI Technique for Identifying the Penumbra in a Rat Model of Acute Ischemic Stroke. Issue 9 (September 2013)

• Record Type: Journal Article
• Authors: Deuchar, Graeme A; Brennan, David; Griffiths, Hugh; Macrae, I Mhairi; Santosh, Celestine
• Is Part Of: Journal of cerebral blood flow & metabolism. Volume 33:Issue 9(2013)
• Page Start: 1422
• Page End: 1428
• Publication Date: 2013-09
• Subjects: acute stroke -- BOLD contrast -- brain imaging -- focal ischemia -- MRI; Cerebral circulation -- Periodicals; Brain -- Metabolism -- Periodicals; Brain -- Blood-vessels -- Periodicals; Cerebrovascular disease -- Periodicals; 612.824
• DOI: 10.1038/jcbfm.2013.86
• Languages: English
• ISSNs: 0271-678X

Abstract

Accurate imaging of ischemic penumbra is crucial for improving the management of acute stroke patients. T2 * magnetic resonance imaging (MRI) combined with a T2 * oxygen challenge (T2 * OC) is being developed to detect penumbra based on changes in blood deoxyhemoglobin. Using 100% O2, T2 * OC-defined penumbra exhibits ongoing glucose metabolism and tissue recovery on reperfusion. However, potential limitations in translating this technique include a sinus artefact in human scans with delivery of 100% OC and relatively small signal changes. Here we investigate whether an oxygen-carrying perfluorocarbon (PFC) emulsion can enhance the sensitivity of the technique, enabling penumbra detection with lower levels of inspired oxygen. Stroke was induced in male Sprague-Dawley rats ( n =17) with ischemic injury and perfusion deficit determined by diffusion and perfusion MRI, respectively. T2 * signal change was measured in regions of interest (ROIs) located within ischemic core, T2 * OC-defined penumbra and equivalent contralateral areas during 40% O2 ± prior PFC injection. Region of interest analyses between groups showed that PFC significantly enhanced the T2 * response to 40% O2 in T2 * -defined penumbra (mean increase of 10.6 ± 2.3% compared to 5.6 ± 1.5% with 40% O2, P <0.001). This enhancement was specific to the penumbra ROI. Perfluorocarbon emulsions therefore enhances the translational potential of the T2 * OC technique for identifying penumbra in acute stroke patients.