Saeed Kalantari1, Cornelia Laule2, Thorarin Albert Bjarnason3, Alex Lloyd MacKay1,2
1Department of Physics and Astronomy, University of British Columbia Hospital, Vancouver, BC, Canada; 2Department of Radiology, University of British Columbia Hospital, Vancouver, BC, Canada; 3Department of Electrical and Computer Engineering, University of Calgary, Calgary, AB, Canada
In this study we developed an analytical approach to measure cross relaxation between myelin tissue and myelin water, myelin water and intra/extra-cellular (I/E) water, and I/E water and non-myelin tissue in five different brain white matter structures from 57 healthy volunteers. Our findings clearly prove the role of exchange in transferring magnetization between the four signal pools. The cross relaxation times between myelin water and I/E water obtained for all examined structures were much longer than the typical T2 values of white matter and hence the calculated cross relaxation correction for the myelin water fraction is minimal.