Windowed stochastic proton decoupling for in vivo (13)C magnetic resonance spectroscopy with reduced RF power deposition.

摘要

PURPOSE: To propose a strategy for reducing radiofrequency (RF) power deposition by stochastic proton decoupling based on Rayleigh's theorem. MATERIALS AND METHODS: Rayleigh's theorem was used to remove frequency components of stochastic decoupling over the 3.90-6.83 ppm range. [2-(13)C] or [2,5-(13) C(2) ]glucose was infused intravenously to anesthetized rats. (13)C labeling of brain metabolites was detected in the carboxylic/amide spectral region at 11.7 T using either the original stochastic decoupling method developed by Ernst or the proposed windowed stochastic decoupling method. RESULTS: By restricting frequency components of stochastic decoupling to 1.91-3.90 ppm and 6.83-7.60 ppm spectral regions decoupling power deposition was reduced by approximately 50%. The proposed windowed stochastic decoupling scheme is experimentally demonstrated for in vivo (13)C MRS of rat brain at 11.7 T. CONCLUSION: The large reduction in decoupling power deposition makes it feasible to perform stochastic proton decoupling at very high magnetic fields for human brain (13)C MRS studies.