Dynamic B0 field inhomogeneities due to vigorous body motion - after mechanical head stabilisation - introduce severe artefacts in accelerated fMRI of awake behaving non-human primates (NHPs) by invalidating the calibration data used for unaliasing reconstruction. Here, we propose a method to estimate dynamic field perturbations via model-based frame-to-frame comparison of EPI reference navigators. These estimates can be used to improve reconstruction quality by matching each data frame to the calibration data, and simultaneously correcting the geometric distortions. The proposed method successfully estimates field perturbations and improves reconstruction quality in accelerated NHP fMRI, without the need for sequence modification or extra acquisitions.
This abstract and the presentation materials are available to members only; a login is required.