Table 1.
Imaging parameters for the in vivo acquisitions, using two field strengths (3T and 7T) and 5 echoes and 10 echoes.
| field strength / number of echoes1 | 3T 5E | 3T 10E | 7T 5E | 7T 10E |
| acquired voxel size [mm] | 0.69 × 0.69 × 2.00 | 0.69 × 0.69 × 2.00 | 0.69 × 0.69 × 2.00 | 0.69 × 0.69 × 2.00 |
| reconstructed voxel size2 [mm] | 0.43 × 0.43 × 1.00 | 0.43 × 0.43 × 1.00 | 0.43 × 0.43 × 1.00 | 0.43 × 0.43 × 1.00 |
| field of view [mm] | 220 × 176 | 220 × 176 | 220 × 176 | 220 × 176 |
| number of echoes | 5 | 10 | 5 | 10 |
| acquisition matrix | 320 × 320 × 86 | 320 × 320 × 86 | 320 × 320 × 74 | 320 × 320 × 74 |
| repetition time [ms] | 24.48 | 45.08 | 24.55 | 45.03 |
| echo time [ms] | 3.85 / 7.97 / 12.09 / 16.21 / 20.33 | 3.85 / 7.97 / 12.09 / 16.21 / 20.33 / 24.45 / 28.57 / 32.69 / 36.81 / 40.93 | 3.81 / 7.91 / 12.00 / 16.10 / 20.20 | 3.81 / 7.91 / 12.00 / 16.10 / 20.20 / 24.29 / 28.39 / 32.48 / 36.58 / 40.68 |
| acceleration factor (phase) | 2 | 2 | 2 | 2 |
| partial k-space3 [%] | 75.15 | 75.15 | 69.96 | 69.96 |
| flow compensation4 | Readout | Readout | Readout | Readout |
| flip angle | 15° | 15° | 15° | 15° |
| pixel bandwidth [Hz/pixel] | 244.14 | 244.14 | 244.14 | 244.14 |
| scan time | 3m35s | 6m36s | 2m51s | 5m15s |
| reconstruction5 | Mag/Real/Imag | Mag/Real/Imag | Mag/Real/Imag | Mag/Real/Imag |
| reconstructed matrix | 512 × 512 × 172 | 512 × 512 × 172 | 512 × 512 × 148 | 512 × 512 × 148 |
| receiver coil6 | 32 channel head | 32 channel head | 32 channel head | 32 channel head |
1
5E = 5 echoes, 10E = 10 echoes.
2
reconstructed voxel size is after Fourier zero-filling by the scanner.
3
using elliptical k-space sampling.
4
flow compensation is performed for all echoes.
5
Mag=Magnitude, Imag=Imaginary.
6
at 3T, RF transmit was performed using the body coil while, at 7T, both RF transmit and reception was performed using a 2-channel transmit/32-channel receive coil.