Reproducibility and repeatability of 3D-GraSE and 2D-EPI ASL on 1.5T and 3T systems in healthy elderly

We present the results of a reproducibility and repeatability study in 34 healthy elderly scanned on 1.5T and 3T systems employing pCASL with a 3D-GraSE and 2D-EPI read-out. Best repeatability and reproducibility were achieved when using 3D-GraSE readout on 3T systems leading to an average repeatability and reproducibility of GM CBF of 2.7% ± 1.8% and 2.9% ± 3.5% respectively. The repeatability and reproducibility of 2D read-out and of comparisons at 1.5T and 1.5T versus 3T were slightly lower. These results imply that 3D-GraSE pCASL at 3T should be preferred in multi-center trials as well as for clinical imaging.