On The Optimal Readout Trajectory for Hyperpolarised 13C Metabolic Imaging

Motivation: Determine the optimal readout trajectory for metabolic imaging with hyperpolarised [1-13C]pyruvate in humans. Goal(s): Implement and compare the two most common efficient spatial encoding schemes: spiral and EPI. Approach: One metabolite in one slice is excited via a spectral-spatial pulse combined with a single-shot readout trajectory. For most comparable results, both spiral and EPI were alternated in a single sequence following one injection of hyperpolarised [1-13C]pyruvate. Results: Spirals exhibit better SNR while EPI shows more image features, pointing to better spatial resolution. Impact: 13C metabolic imaging provides valuable clinical information, such as tumour-treatment response, and may complement or provide an alternative to PET. For clinical studies, it is important to choose the optimal sequence.