Figure 1: Automatic processing pipeline: The ICBM 2009a nonlinear symmetric MNI template was non-linearly registered to the subject’s T1w space (using Vida_64Ch as reference). Inter/Intra-run co-registrations were performed (T1wRef-to-T1w, as well as T1w-to-R2*). Tissue segmentation was achieved using SPM12 software using the default brain probability maps. Labels were propagated to R2*/QSM space and restricted to WM/GM tissue types. WM/GM lobes and cerebellum were extracted, as well as four deep grey nuclei and the brainstem prior ROI analysis on the quantitative maps.

Reproducibility across MR system types (Verio and Vida), receive head coils (20, 32 and 64 channels) and sequence parameters. Note that the measured variability on the Vida with different head coils was not different than the intra-run metric variations on the Verio system. The signal drop caused by the increased acceleration factor from 3 to 4 was not reflected in the R2* and QSM estimations, with values in the same range as the other protocols. The central table reports mean and standard deviation per segmented region across all measurements.