One of the specific goals of this core was spatial localization based on Bo phase encoding and Fourier Series Window (FSW) reconstruction in the phase encode dimension, using uneven and optimized k-space sampling during data acquisition, and arbitrary, operator defined, voxel shifting by post-acquisition processing. In the previous years, we established this methodology in 1D, 2D, 3D, establishing the capability to generate cylindrical voxels. Spectroscopic studies with phantoms illustrated excellent spatial localization, with no detectable out-of-voxel contamination and the technique was implemented in human and animal model studies, demonstrating the technique's utility. In the previous year, we applied this technique to investigate human brain bioenergetics using 31P spectroscopy. The method yielded sufficiently good SNR, despite the inherently low sensitivity of the 31P nuclei, to permit the investigation of phosphorylated metabolite changes as well as the measurement of the unidirectional rate of creatine kinase (CK) catalyzed ATP synthesis from creatine phosphate (CP) during photic stimulation. We were able to demonstrate that while the metabolite contents did not show a change, CK mediated CP-to-ATP rate increased during photic stimulation, suggesting that ADP levels may have increased simultaneously with H+ increase, keeping CP level constant but reflecting the ADP increase in the CK mediated CP-to-ATP rate.
NIH ExPorter
NIH ExPorter