Dynamic Distortion Correction of SE EPI Data using Phase Maps from Simultaneously-Acquired GE-EPI Data

Jack Harmer¹, Susan Francis¹, Richard Bowtell¹

EPI acquisitions are highly susceptible to image distortions due to the presence of B0-field inhomogeneities. A powerful approach which can be used to correct dynamically varying distortions in GE fMRI time series involves exploiting the phase of the EPI data in conjunction with a single reference field-map. We show that this dynamic distortion correction can be applied to SE data by modifying a SE-EPI sequence to acquire a GE-image before the 180 RF pulse and then using the phase of the GE-EPI data to monitor field variation. This method has been tested on SE-EPI data acquired at 7T.