Dynamic oxygen-17 MRI with adaptive temporal resolution using golden-means-based 3D radial sampling.
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ABSTRACT: Purpose
The aim of this study was to develop a high-resolution 3D oxygen-17 (17 O) MRI method to delineate the kinetics of 17 O-enriched water (H2 17 O) across the entire mouse brain after a bolus injection via the tail vein.Methods
The dynamic 17 O signal was acquired with a golden-means-based 3D radial sampling scheme. To achieve adequate temporal resolution with preserved spatial resolution, a k-space-weighted view sharing strategy was used in image reconstruction with an adaptive window size tailored to the kinetics of the 17 O signal. Simulation studies were performed to determine the adequate image reconstruction parameters. The established method was applied to delineating the kinetics of intravenously injected H2 17 O in vivo in the post-stroke mouse brain.Results
The proposed dynamic 17 O-MRI method achieved an isotropic resolution of 1.21 mm (0.77 mm nominal) in mouse brain at 9.4T, with the temporal resolution increased gradually from 3 s at the initial phase of rapid signal increase to 15 s at the steady-state. The high spatial resolution enabled the delineation of the heterogeneous H2 17 O uptake and washout kinetics in stroke-affected mouse brain.Conclusion
The current study demonstrated a 3D 17 O-MRI method for dynamic monitoring of 17 O signal changes with high spatial and temporal resolution. The method can be utilized to quantify physiological parameters such as cerebral blood flow and blood-brain barrier permeability by tracking injected H2 17 O. It can also be used to measure oxygen consumption rate in 17 O-oxygen inhalation studies.
SUBMITTER: Gu Y
PROVIDER: S-EPMC8324328 | biostudies-literature |
REPOSITORIES: biostudies-literature
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