Lindsay Gallagher3, William Holmes3,
1School of Physics, University of Dublin, Dublin, Ireland; 2Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany; 3Glasgow Experimental MRI Centre, University of Glasgow, Glasgow, United Kingdom; 4Centre for Advanced Medical Imaging, St. James's Hospital, Dublin, Ireland
The validity of the perfusion-diffusion mismatch in acute stroke diagnosis has been challenged recently, and an alternative approach to identifying penumbral tissue is desirable. A custom-built dual-tuned surface coil was used to obtain high-quality 1H-DWI and 23Na images in the acute phase of a rat stroke (n=6). The mismatch between the perfusion deficit and ischaemic damage determined from histology was used to define core and penumbral tissue regions at ~5hrs after stroke. The 23Na signal evolved differently in both regions, supporting the hypothesis that under-perfused regions which have not yet exhibited an increase in 23Na signal above normal levels indicate penumbral tissue.