XTC MRI Parameter Optimization: Theoretical Considerations
Ruppert K, Mugler III J, Mata J, Hagspiel K, Brookeman J
Advanced MRI Technologies, University of Virginia
A typical Xenon polarization Transfer Contrast (XTC) MRI experiment consists of 2 imaging segments separated by a contrast preparation segment. In this work we performed a theoretical analysis of how the available non-equilibrium magnetization of hyperpolarized Xe-129 should be expended to obtain maximum sensitivity to regional variations in the gas-phase depolarization. We found that an individual optimization of the flip angles for the two imaging segments and of the number of contrast-generating RF inversion pairs can improve the error in the resulting depolarization maps by about 200% compared to previously-published results.