Irretrievable Signal Loss in Partial-Fourier Acquired Diffusion-Weighted Images

Marcel Peter Zwiers¹, Eelke Visser², David Gordon Norris², Nico Papinutto³, Benedikt Andreas Poser²

Diffusion weighted (DW) partial-Fourier (PF) imaging is highly sensitive to cardiac activity induced signal voids that depend critically on the image reconstruction method. The current explanation is that these artefacts result from incorrect phase estimation. We found that artefacts remained present in the PF acquired images, even when using zero-padding reconstruction or true (ideal) phase information. Cardiac pulsations induce phase gradients that can shift the local low-frequency information into the unacquired part of k-space. The associated signal voids are therefore irretrievable by any PF reconstruction method. Thus, PF DW imaging should generally be avoided or used solely with cardiac gating.