High-resolution dynamic oxygen-17 MR imaging of mouse brain with golden-ratio-based radial sampling and k-space-weighted image reconstruction

PurposeThe current study aimed to develop a three-dimensional (3D) dynamic oxygen-17 (O-17) MR imaging method with high temporal and spatial resolution to delineate the kinetics of O-17 water uptake and washout in the brains of mice with glioblastoma (GBM). MethodsA 3D imaging method with a stack-of-stars golden-ratio-based radial sampling scheme was employed to acquire O-17 signal in vivo. A k-space-weighted image reconstruction method was used to improve the temporal resolution while preserving spatial resolution. Simulation studies were performed to validate the method. Using this method, the kinetics of O-17 water uptake and washout in the brains of mice with GBM were delineated after an intravenous bolus injection of O-17 water. ResultsThe proposed O-17 imaging method achieved an effective temporal resolution of 7.56 s with a nominal voxel size of 5.625L in the mouse brain at 9.4T. Reduced uptake and prolonged washout of O-17 water were observed in tumor tissue, suggesting compromised cerebral perfusion. ConclusionThis study demonstrated a promising dynamic O-17 imaging approach that can delineate O-17 water kinetics in vivo with high temporal and spatial resolution. It can also be used to image cerebral oxygen consumption rate in oxygen-17 inhalation studies. Magn Reson Med 79:256-263, 2018. (c) 2017 International Society for Magnetic Resonance in Medicine.