Rob H.N. Tijssen1, 2, Karla L. Miller1
1FMRIB Centre, Oxford University, Oxford, United Kingdom; 2University Medical Center Utrecht, Utrecht, Netherlands
Recent renewed interest in 3D acquisition methods for FMRI poses the question whether retrospective corrections are better performed in image space (RETROICOR or k-space (RETROKCOR). As 3D acquisitions typically use multi-shot readouts in which the data are combined over a period of several seconds one could argue that a k-space based correction is more appropriate. It was found, however, that RETROICOR performs equally well compared to RETROKCOR suggesting that a single cardiac/respiratory phase for the entire volume is sufficient to generate suitable nuisance regressors for an effective correction of the data.