Table 1.
List of all spectroscopic imaging techniques and their specifications, including: spatial field of view (FOV), spectral bandwidth (BW), number of scan repetitions (NEX), total acquisition time (tACQ), nominal resolution, and effective spatial resolution (as estimated via 3D-PSF simulation in MATLAB). The full-volume at half maximum PSF signal was used to represent effective spatial resolution. For traditional encoded 12×12×8 k-space sampling, ellipsoidal sampling, and SENSE sampling each point represented 9.04×10−6 cm3 (1 cm3 = 483 points). For all other 3D-MRSI techniques, each point represented 30.52×10−6 cm3 (1 cm3 = 323 points).
| Encoding Technique | FOV (cm3) | BW (Hz) | NEX | tACQ (min) | Nominal Resolution | Effective Spatial Resolution |
|---|---|---|---|---|---|---|
| Traditional MRSI | 12×12×8 | 2000 | 1 | 21.12 | 1cm3×1.95Hz | 1.017 cm3 |
| Ellipsoidal MRSI * | 12×12×8 | 2000 | 1 | 9.39 | 1cm3×1.95Hz | 2.473 cm3 |
| SENSE MRSI (Rx=2) * | 12×12×8 | 2000 | 1 | 10.56 | 1cm3×1.95Hz | 1.026 cm3 |
| SENSE w/REG * | 12×12×8 | 2000 | 1 | 10.56 | 1cm3×1.95Hz | 1.026 cm3 |
| Flyback EPSI | 16×16×16 | 988 | 2 | 9.46 | 1cm3×1.39Hz | 1.014 cm3 |
| Symmetric EPSI | 16×16×12 | 977 | 2 | 9.39 | 1cm3×1.91Hz | 1.015 cm3 |
| Symmetric w/ramps ‡ | 16×16×12 | 977 | 2 | 9.39 | 0.857cm3×1.91Hz | 0.868 cm3 |
These data sets were simulated from the traditionally encoded MRSI data.
From same dataset as symmetric EPSI data.