Novel Ischaemic Penumbra Imaging

Novel MRI technique for metabolic imaging of the ischaemic penumbra following stroke

4 images showing. 1. the Quantitative ADC and CBF maps displaying the diffusion & perfusion deficit 1 hour following stroke. 2. the percentage signal change following O2 inhalation during a T2* weighted scan. 3. a higher signal change in the ipsilateral cortex indicative of the ischaemic penumbra. 4. a traditional diffusion/perfusion mismatch technique showing an approximation of the penumbra.
We have been developing novel imaging techniques for imaging tissue metabolism following stroke using O2 inhalation combined with T2* weighted imaging.  Quantitative ADC (left) and CBF (middle) maps show the diffusion & perfusion deficit at 1 hour following stroke in the rat.  Image on the right shows the % signal change following O2 inhalation during T2* weighted imaging (sensitive to the ratio of oxy/deoxyhaemoglobin in tissue).  Note the higher signal change in the ipsilateral cortex indicative of the ischaemic penumbra (highlighted in green).  The traditional diffusion/perfusion mismatch technique shows an approximation of the penumbra in black (bottom right).

This technique has now been developed with significant investment from the Wellcome Trust and private investors into a spin out company, Aurum Biosciences (www.aurumbiosciences.com).

Relevant references:  

Baskerville, T.Deuchar, G. A.McCabe, C., Robertson, C. A., Holmes, W. M.Santosh, C., and Macrae, I. M. (2011) Influence of 100% and 40% oxygen on penumbral blood flow, oxygen level, and T2*-weighted MRI in a rat stroke model. Journal of Cerebral Blood Flow and Metabolism, 31 (8). pp. 1799-1806. ISSN 0271-678X (doi:10.1038/jcbfm.2011.65)

Robertson, C. A., McCabe, C.Gallagher, L.Lopez Gonzalez, M. d.Holmes, W. M.Condon, B.Muir, K. W.Santosh, C., and Macrae, I. M.(2011) Stroke penumbra defined by an MRI-based oxygen challenge technique: 2. Validation based on the consequences of reperfusion.Journal of Cerebral Blood Flow and Metabolism, 31 (8). pp. 1788-1798. ISSN 0271-678X (doi:10.1038/jcbfm.2011.67)

Robertson, C. A., McCabe, C.Gallagher, L., Lopez-Gonzalez, M. d., Holmes, W. M.Condon, B.Muir, K. W.Santosh, C., and Macrae, I. M. (2011) Stroke penumbra defined by an MRI-based oxygen challenge technique: 1. validation using [14C]2-deoxyglucose autoradiography. Journal of Cerebral Blood Flow and Metabolism, 31 . pp. 1778-1787. ISSN 0271-678X (doi:10.1038/jcbfm.2011.66)

Santosh, C., Brennan, D., McCabe, C., Macrae, I.M., Holmes, W.M., Graham, D., Gallagher, L., Condon, B.,  Hadley, D.M., Muir, K.W., Gsell, W. (2008) Potential use of oxygen as a metabolic biosensor in combination with T2*-weighted MRI to define the ischemic penumbra. Journal of Cerebral Blood Flow and Metabolism, 28 (10). pp. 1742-1753. ISSN 0271-678X (doi:10.1038/jcbfm.2008.56)

Deuchar GA, Brennan D, Holmes WM, Shaw M, Macrae IM, Santosh C. Perfluorocarbon Enhanced Glasgow Oxygen Level Dependent (GOLD) Magnetic Resonance Metabolic Imaging Identifies the Penumbra Following Acute Ischemic Stroke. Theranostics. 2018 Feb 12;8(6):1706-1722. doi: 10.7150/thno.21685