Inna V. Linnik1,2,
Marietta Scott3, Neil Woodhouse4, John C. Waterton3,5,
Helen Young3, Carsten Liess3, Herv Barjat3,
Jose Ulloa3, Cassandra L. Hodgkinson6, Timothy Ward6,
Caroline Dive6, Darren Roberts6, Josephine H. Naish1,7,
Geoffrey J. M. Parker5,8
1Imaging
Science & Biomedical Engineering, School of Cancer & Enabling Sciences, University of Manchester, Oxford Road,
Manchester M13 9PT, United Kingdom; 2Biomedical
Imaging Institute, University of
Manchester, Oxford Road, Manchester
M13 9PT, United Kingdom; 3Imaging, Translational Sciences,
AstraZeneca, Alderley Park, Macclesfield, Cheshire, SK10 4TG, United Kingdom;
4Imaging, Translational Sciences, AstraZeneca, Alderley Park,
Macclesfield, Cheshire, SK10 4TG , United Kingdom; 5Imaging
Science & Biomedical Engineering, School of Cancer & Enabling
Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom; 6Paterson
Institute for Cancer Research, Manchester, United Kingdom; 7Biomedical
Imaging Institute, University of Manchester, Oxford Road, Manchester M13 9PT,
United Kingdom; 8Biomedical Imaging Institute , University of
Manchester, Oxford Road, Manchester M13 9PT, United Kingdom
Dynamic oxygen-enhanced (OE) MRI monitors the tissue change in longitudinal relaxation rate (R1) when switching from breathing air to 100 % O2. It was shown using dynamic OE-MRI that some tumour regions demonstrate an R1 increase under O2 inhalation consistent with the delivery of paramagnetic molecular oxygen via the blood plasma. However, our recent studies have demonstrated that tumours also exhibit regions that paradoxically reduce R1 with the switch to O2. Here we provide a theoretical explanation of this difference in response between regions and demonstrate that OE-MRI may provide a new non-invasive method for quantifying hypoxic extent in tumours.
Keywords