Here we show the different off-resonance effects from EPI vs. spiral acquisition. In the EPI image, geometric distortion of the brain is visible with a distortion sensitivity of 75 Hz/cm (see Eq. (9)), a typical value, resulting in the brain being stretched compared to the original Cartesian spin-warp image (blue arrows). In the spiral image, there is a large amount of blurring, noted by the red arrow, but there is less geometric distortion than in EPI.