Human in vivo phosphate metabolite imaging with ³¹P NMR

Phosphorus (³¹P) spectroscopic images showing the distribution of high‐energy phosphate metabolites in the human brain have been obtained at 1.5 T in scan times of 8.5 to 34 min at 27 and 64 cm³ spatial resolution using pulsed phase‐encoding gradient magnetic fields and three‐dimensional Fourier transform (3DFT) techniques. Data were acquired as free induction decays with a quadrature volume NMR detection coil of a truncated geometry designed to optimize the signal‐to‐noise ratio on the coil axis on the assumption that the sample noise represents the dominant noise source, and self‐shielded magnetic field gradient coils to minimize eddy‐current effects. The images permit comparison of metabolic data acquired simultaneously from different locations in the brain, as well as metabolite quantification by inclusion of a vial containing a standard of known ³¹P concentration in the image array. Values for the NMR visible adenosine triphosphate in three individuals were about 3 mM of tissue. The ratio of NMR detectable phosphocreatine to ATP in brain was 1.15 ± 0.17 SD in these experiments. Potential sources of random and systematic error in these and other ³¹P measurements are identified. © 1988 Academic Press, Inc.