We
established a practical protocol for quantitatively imaging the cerebral
metabolic rates of ATP production via ATPase and creatine kinase (CK) reactions
in human brain at 7T using three dimensional (3D) chemical shift imaging (CSI)
and in vivo 31P MR
spectroscopy (MRS) in combine with magnetization transfer (MT) approach.
Subsequently, we applied this 3D 31P-MT imaging protocol to quantify
the regional phosphorous metabolites concentrations, ATPase and CK reaction
rate constants and fluxes and the intracellular pH in human brain at rest and
during visual stimulation. The results
of this study provide the values of key parameters relevant to ATP metabolism
in absolute scale, which allow quantitative evaluation of regional cerebral
energetics in resting human brain and its functional changes.
