Application of two-dimensional CSI for absolute quantification of phosphorus metabolites in the human liver

There, have recently been a number of studies dealing with the absolute qua ntification of concentrations of MR-visible phosphorus compounds, in differ ent tissues. The use of absolute values rather than intensity ratios may fu rnish additional information about metabolic changes associated with, diffe rent diseases. The purpose of this study was to develop a general procedure for measuring molar metabolite concentrations, and to apply it with respec t to the evaluation of human liver P-31-MRS data measured using a standard slice-selective two-dimensional CSI sequence and commercial H-1/P-31 surfac e coil. The experimental determination of all surface coil-related factors. influencing signal intensity was undertaken using a gradient echo imaging technique that can be adapted to, commercial systems. The resulting values for healthy volunteers (N=9) showed concentrations of PME = 2.8 +/-1.3 mM, PDE = 9.9 +/-2.7 mM, P-i = 1.7 +/-0.7 mM, and ATP = 3.6 +/-0.9 mM in the hu man liver. The data are quite consistent with published findings. (C) 2001 Elsevier Science B.V. All rights reserved.