Field-mapping techniques using a reference scan allow accurate distortion correction of EPI data. However, due to the strong B0 dependency with head motion and other physiological artefacts in fMRI acquisitions, the reference field-map does not adequately correct for dynamic non-linear changes in image intensity. In this work we show the feasibility of a method to map temporal variations of the B0-field at 7 Tesla, using a high-resolution Multi-echo EPI sequence, acquiring three echo-modules with reverse phase-encoding direction on the second echo. The robustness of the method was tested during an fMRI acquisition with visual presentation of faces.
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