A 3D hybrid-shot spiral sequence for hyperpolarized 13C imaging

Area of Science:

• Medical Imaging
• Magnetic Resonance Imaging
• Hyperpolarized Contrast Agents

Background:

• Hyperpolarized imaging demands high spatial, temporal, and spectral resolution, presenting a significant technical challenge.
• Spectral-spatial Radio Frequency (RF) excitation is a promising technique for magnetization-efficient hyperpolarized imaging.
• The optimal readout strategy for spectral-spatial RF excitation in hyperpolarized imaging remains undetermined.

Purpose of the Study:

• To develop and evaluate a novel 3D hybrid-shot spiral sequence for hyperpolarized imaging.
• To address the conflicting resolution requirements in hyperpolarized imaging experiments.
• To offer greater flexibility in data acquisition and image reconstruction.

Main Methods:

• Proposed a novel 3D hybrid-shot spiral sequence with two constant density regions.
• Enabled retrospective reconstruction of either high spatial or high temporal resolution images post hoc.
• Implemented and validated the sequence through simulation and preclinical scanning.

Main Results:

• Demonstrated the feasibility of the proposed sequence in a Hydrogen-1 (1H) phantom.
• Successfully applied the sequence to hyperpolarized Carbon-13 (13C) pyruvate imaging in vivo.
• Confirmed the capability for adaptive spatiotemporal imaging.

Conclusions:

• The developed sequence effectively ameliorates the conflict between spatial and temporal resolution in hyperpolarized imaging.
• Adaptive spatiotemporal imaging offers enhanced flexibility for acquiring hyperpolarized datasets.
• The sequence shows significant potential for future clinical translation.