G. A. Deuchar, D. Brennan, H. Griffiths, I. M. Macrae, C. Santosh


1559-7016 (Electronic)0271-678X (Linking)

Publication year



J Cereb Blood Flow Metab

Periodical Number






Author Address

Wellcome Surgical Institute, Glasgow Experimental MRI Centre, Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.

Full version

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.