Table 1.
Summary of EPI brain studies. All brain data were acquired with 1.5 × 1.5 cm2 in-plane resolution using a constant 20° pyruvate/30° lactate/30° bicarbonate flip angle scheme and an integrated birdcage and 32 channel head coil. Time-to-peak (TTP) signal is referenced from the start of acquisition, and the reported polarization is referenced to the start of dissolution. The error in center frequency calibration (Δf) was measured with non-localized spectroscopy following dynamic imaging.
| Δf (Hz) |
13C Polarization |
Time to injection |
Pyruvate | Lactate | Bicarbonate | ||||
|---|---|---|---|---|---|---|---|---|---|
| Peak SNR |
TTP | Peak SNR |
TTP | Peak SNR |
TTP | ||||
| Study #1 | +3.7 | 41.3% | 54s | 447 | 9s | 30 | 12s | 6 | 15s |
| Study #2 | +3.7 | 41.9% | 60s | 396 | 3s | 28 | 6s | 7 | 9s |
| Study #3 | +6.1 | 33.1% | 53s | 402 | 9s | 16 | 9s | 8 | 15s |