Markus Nikola Streicher1, Andreas Schfer1, Bibek Dhital1, Dirk Mller1, Robin Martin Heidemann1, Andre Pampel1, Dimo Ivanov1, Robert Turner1
1Max Planck Institute for Human
Cognitive and Brain Sciences,
We implemented a novel spin-echo EPI sequence that can acquire phase images of different chemically-shifted protons at the same slice positions. Chemical selection was achieved by applying different slice-select gradient amplitudes for excitation and refocusing RF pulses, and phase sensitivity was obtained using an asymmetric EPI readout. MR Thermometry was then performed on a mixture of water and dimethyl sulfoxide (DMSO), which has a proton chemical shift of -2 ppm from water. The two compounds were then imaged alternately, water for temperature sensitivity and DMSO to monitor field changes. Fat can also be selectively imaged as a reference compound.