In Vivo Myelin Water Imaging Using Z-Shimmed Multi-Gradient-Echo Pulse Sequences at 3T

Quantitative imaging of the myelin water fraction (MWF) is able to show demyelinating processes and therefore provides insight into the pathology of white matter (WM) diseases such as multiple sclerosis. So far, mapping of the MWF most often was performed using a multi-echo spin-echo sequence and fitting the biexponential T2 decay with a non-negative least-squares algorithm. In this work, a different approach is presented using multi-gradient-echo pulse sequences. This method has been introduced by one study measuring formalin-fixed brains. We present a solution for in vivo measurements using z-shimming as a correction for magnetic field inhomogeneities