Table 2.
Mean and standard deviation values for longitudinal T1ρ relaxation, transverse T2ρ relaxation, correlation time constant τc,b, exchange time constant τex, exchange chemical shift δωex, water bound fraction Pb. Values are calculated in eight ROIs segmented by Freesurfer 5.1 on high-resolution 3D anatomical scans and coregistered to the 3D rotating frame relaxation maps acquired in the brains of five human volunteers. Only voxels with a coefficient of determination R2 > 0.95 were used for statistical analysis. Voxels at the boundary of ROIs were also excluded. RH – right hemisphere, LH – left hemisphere, Ventral DC – ventral diencephalon, SN – substancia nigra.
| Brain ROI | T1ρ (ms) | T2ρ (ms) | τc,b (ns) | τex (ms) | δωex (ppm) | Pb | |
|---|---|---|---|---|---|---|---|
| White Matter | RH | 79.5 ± 5.5 | 73.9 ± 7.5 | 2.40 ± 0.15 | 0.21 ± 0.01 | 0.42 ± 0.02 | 0.125 ± 0.005 |
| LH | 79.0 ± 5.4 | 73.9 ± 7.4 | 2.41 ± 0.15 | 0.21 ± 0.01 | 0.42 ± 0.02 | 0.126 ± 0.005 | |
| Gray Matter | RH | 96.1 ± 16.9 | 90.4 ± 15.8 | 2.13 ± 0.18 | 0.18 ± 0.03 | 0.36 ± 0.04 | 0.109 ± 0.013 |
| LH | 95.3 ± 13.9 | 90.3 ± 15.1 | 2.11 ± 0.15 | 0.18 ± 0.02 | 0.36 ± 0.03 | 0.108 ± 0.010 | |
| Thalamus | RH | 80.8 ± 6.2 | 80.5 ± 8.6 | 2.29 ± 0.14 | 0.20 ± 0.01 | 0.41 ± 0.02 | 0.122 ± 0.006 |
| LH | 80.3 ± 6.0 | 80.0 ± 8.1 | 2.29 ± 0.15 | 0.20 ± 0.01 | 0.41 ± 0.02 | 0.122 ± 0.006 | |
| Caudate | RH | 90.7 ± 5.9 | 84.2 ± 9.5 | 2.16 ± 0.11 | 0.19 ± 0.01 | 0.37 ± 0.02 | 0.112 ± 0.005 |
| LH | 90.9 ± 6.3 | 82.9 ± 8.9 | 2.15 ± 0.12 | 0.19 ± 0.01 | 0.37 ± 0.02 | 0.111 ± 0.005 | |
| Putamen | RH | 85.8 ± 6.5 | 80.4 ± 8.6 | 2.18 ± 0.11 | 0.19 ± 0.01 | 0.39 ± 0.02 | 0.116 ± 0.006 |
| LH | 84.5 ± 6.2 | 80.0 ± 9.2 | 2.18 ± 0.11 | 0.20 ± 0.01 | 0.39 ± 0.02 | 0.117 ± 0.005 | |
| Pallidum | RH | 69.8 ± 3.7 | 64.5 ± 5.8 | 2.55 ± 0.15 | 0.22 ± 0.01 | 0.45 ± 0.01 | 0.134 ± 0.004 |
| LH | 68.7 ± 3.9 | 64.0 ± 5.3 | 2.59 ± 0.17 | 0.23 ± 0.01 | 0.45 ± 0.02 | 0.136 ± 0.005 | |
| Hippocampus | RH | 91.8 ± 8.2 | 86.8 ± 13.7 | 2.14 ± 0.13 | 0.19 ± 0.01 | 0.37 ± 0.02 | 0.111 ± 0.006 |
| LH | 87.2 ± 7.7 | 72.2 ± 14.1 | 2.11 ± 0.13 | 0.19 ± 0.01 | 0.38 ± 0.02 | 0.113 ± 0.006 | |
| Ventral DC (SN) | RH | 73.4 ± 7.4 | 69.9 ± 10.7 | 2.48 ± 0.21 | 0.22 ± 0.01 | 0.43 ± 0.03 | 0.130 ± 0.008 |
| LH | 72.1 ± 7.3 | 67.2 ± 10.4 | 2.50 ± 0.21 | 0.22 ± 0.01 | 0.44 ± 0.03 | 0.132 ± 0.008 | |