Integration of Higher-Order Dynamic Fields Into MR Image Reconstruction

Bertram Jakob Wilm¹, Christoph Barmet¹, Matteo Pavan¹, Peter Boesiger¹, Klaas Paul Pruessmann¹

Recent improvements in magnetic field monitoring opened up the possibility of capturing higher-order dynamic field evolution, providing the necessary information to correct for the image distortions they cause. In the present work a technique for higher order field reconstruction is introduced and demonstrated for diffusion weighted EPI. It has been found that eddy currents of diffusion gradients can induce considerable higher-order field perturbations, causing residual error in conventional first-order reconstruction. Higher-order reconstruction largely eliminated these errors in phantom and in-vivo experiments.