Magnetic Field Monitoring of Radial Trajectories

Daniel Giese¹, ², Christoph Kolbitsch¹, Andrew Aitken¹, Martin Buehrer², Tobias Schaeffter¹, Sebastian Kozerke¹, ²

Radial k-space trajectories are widely used in motion correction applications and for undersampled acquisitions given the repeated sampling of the centre of k-space. Radials are, however, prone to eddy currents and gradient delays effects. In this work, we analyze the miscentering of k-space using a 3rd order magnetic field camera, measuring k-space and quantifying gradient delays and eddy currents. Single slice, dual slice and cardiac cine images are acquired in-vivo and corrected using the measured trajectories reducing the level of artifacts. The method uses a single preparation scan to acquire k-space and can be used for any angular spoke distribution and level of undersampling.