Hyperpolarized 129Xe gas lung MRI-SNR and T2*comparisons at 1.5 T and 3 T

In this study, the signal-to-noise ratio of hyperpolarized Xe-129 human lung magnetic resonance imaging was compared at 1.5 T and 3 T. Experiments were performed at both B0 fields with quadrature double Helmholtz transmitreceive chest coils of the same geometry with the same subject loads. Differences in sensitivity between the two field strengths were assessed from the signal-to-noise ratio of multi-slice 2D Xe-129 ventilation lung images obtained at the two field strengths with a spatial resolution of 15 mm x 4 mm x 4 mm. There was a systematically higher signal-to-noise ratio observed at 3 T than at 1.5 T by a factor of 1.25. Mean image signal-to-noise ratio was in the range 2744 at 1.5 T and 3651 at 3 T. T-2* of 129Xe gas in the partially inflated lungs was measured to be 25 ms and 18 ms at 1.5 T and 3 T, respectively. T-2* of Xe-129 gas in fully inflated lungs was measured to be 52 ms and 24 ms at 1.5 T and 3 T, respectively. Magn Reson Med, 2012. (c) 2012 Wiley Periodicals, Inc.