Combined Eddy-Current and EPI-PSF-Based Distortion Corrections in Quantification of DW EPI at UHF

Oleg Posnansky¹, Myung-Ho In¹, Oliver Speck¹

Single-shot spin-echo echo-planar imaging allows for very fast signal acquisition and is frequently used in diffusion-weighting (DW) MRI. However, it is prone to severe distortions due to local variations in the static magnetic field, eddy currents induced by the DW gradients, susceptibility, and chemical shift, especially at ultra-high magnetic field. Geometric incongruence in DW images may impose significant errors in calculations of diffusion tensors and their derived metrics. We demonstrate that these imperfections can be corrected effectively by a combination of eddy-current correction and improved point-spread function mapping.