Table 1.
Phantoms employed, as depicted in Fig. 2, with fitted values from region of interest (ROI) evaluations and exchange rates of creatine predicted by water exchange spectroscopy (WEX) studies (39). Fits by a two-pool Bloch–McConnell simulation were performed simultaneously for five Z-spectra obtained with B1 = 0.2, 0.4, 0.6, 0.8 and 1.0 µT in each ROI
| Phantom/ROI | pH | [Cr] (mm) | [Ag] (%) | kb (WEX) (s−1) | kb (CEST) (s−1) | fb (%) | R2b (s−1) | R2a (s−1) | T1a (s) |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 6.38 | 55.5 | 0 | 35.1 | 33.8 | 0.22 | 40.3 | 0.60 | 2.92 |
| A1 | 6.38 | 55.5 | 0.2 | 35.1 | – | – | – | 2.47 | 2.99 |
| A2 | 6.38 | 55.5 | 0.4 | 35.1 | – | – | – | 3.57 | 2.97 |
| A3 | 6.38 | 55.5 | 0.6 | 35.1 | – | – | – | 4.82 | 2.92 |
| A4 | 6.38 | 55.5 | 0.8 | 35.1 | – | – | – | 6.23 | 2.87 |
| A5 | 6.38 | 55.5 | 1.0 | 35.1 | – | – | – | 7.58 | 2.83 |
| F1 | 6.38 | 55.5 (1/3) | 0 | 35.1 | 38.5 | 0.073 | 58 | 0.42 | 3.00 |
| F2 | 6.38 | 55.5·(2/3) | 0 | 35.1 | 46.5 | 0.13 | 53 | 0.42 | 2.99 |
| PH1 | 6.21 | 55.5 | 0 | 23.72 | 31.6 | 0.18 | 49 | 0.44 | 2.91 |
| PH2 | 6.32 | 55.5 | 0 | 30.6 | 34.8 | 0.20 | 48 | 0.43 | 2.93 |
| PH3 | 6.61 | 55.5 | 0 | 59.6 | 63.0 | 0.21 | 54 | 0.46 | 2.93 |
−, missing fitting data when the two-pool model was insufficient.