Lauren Jean Bains1, Deirdre M. McGrath1, Josephine H. Naish1, Susan Cheung1, M B. Taylor2, J P. Logue2, Geoff J M Parker1, John C. Waterton1,3, David L. Buckley1
1Imaging Science and Biomedical Engineering, School of Cancer and Imaging Sciences, University of Manchester, Manchester, UK; 2Christie Hospital, Manchester, UK; 3AstraZeneca, Alderley Park, Macclesfield, Cheshire, UK
Because contrast agent concentration is measured indirectly in MRI via its effect on the surrounding water molecules, the rate of water exchange between tissue compartments can affect quantitative parameters calculated using DCE-MRI data. Since DCE-CT is not affected by water exchange, a comparison was made between DCE-MRI and DCE-CT to assess the impact of water exchange on DCE-MRI data. Two limiting cases of water exchange were examined; at one limit, flow may be underestimated while at the other limit blood volume was overestimated. Preliminary attempts failed to estimate water exchange rates, suggesting the need for further water exchange sensitive data.