Figure 7:

Results of hyperpolarized [1-¹³C]pyruvate studies on a healthy human volunteer using the proposed method (Fig. 1) with in-house built birdcage transmit coil and 32-channel receive array. In this study, single-slice real-time B₁ calibration was triggered right after real-time center frequency calibration. The ROI for both bolus tracking and B₁ calibration was on the brain tissue near the superior sagittal sinus of slice 5 (see Fig. 8 for slice 1–8). A multi-slice 2D acquisition was used for pyruvate/lactate/bicarbonate dynamic imaging. Initial power was the same as the calibrated power in pre-scan. Sequence parameters are presented in Table 2. (a) Proton image of slice 5. (b) Normalized ¹³C B₁ maps. (c) Acquired frequency spectrum for center frequency calibration. (d) ¹³C results of slice 5 displayed in the order of time. Multi-slice dynamic images can be found in Sup. Fig. S3. Sum-over-time images can be found in Fig. 8. Experiment recordings: https://youtu.be/Oq36Z7ayQ0g.