The mGRE data for mapping the decay curves were acquired with an in-house developed pulse-sequence (van Gelderen et al., 2012 (link)). Echo times (TEs) ranged from 2.3 to 62.7 ms. Thirty-eight echoes (positive read gradient only) were acquired with an echo spacing of 1.6 ms. Repetition time (TR) was 1 s and flip angle (FA) was 70°. Fifteen slices with 1.5 mm slice thickness and 25% gap between slices were measured per scan, with an in-plane resolution of 1.5 × 1.5 mm and a FOV of 240 × 180 mm (the acquisition matrix size is 160 × 120). The slices were parallel to the plane of the anterior and posterior commissure line and captured a section of the corpus callosum. Five signal averages were acquired within a total scan time of 10 min.
Whole brain 3D T1-weighted magnetization-prepared rapid gradient echo (T1-MPRAGE) was acquired before (pre-gad T1) and after (post-gad T1) contrast injection (0.1 mmol/kg gadobutrol; Bayer Healthcare, Leverkusen, Germany).