Compressed sensing reconstruction for high-SNR, rapid dissolved 129Xe gas exchange MRI

Motivation: 3D hyperpolarized 129Xe gas exchange imaging is limited by low SNR and long breath-holds, which is problematic for patients with dyspnea and/or low gas transfer. Compressed sensing (CS) reconstruction can accelerate 129Xe MRI whilst improving SNR. Goal(s): To assess whether gas exchange ratio maps are quantitatively preserved with CS dissolved 129Xe imaging and investigate the feasibility of reduced-cost natural abundance (NA) CS dissolved 129Xe imaging. Approach: CS-reconstructed gas exchange ratios were evaluated in healthy volunteers and COPD patients and prospectively with NA 129Xe. Results: CS increased image SNR, allowed 3-fold acquisition acceleration and maintained ratio map fidelity, even with NA 129Xe. Impact: Compressed sensing reconstruction of dissolved 129Xe spectroscopic imaging improved image quality even with decreased scan time, whilst preserving key gas exchange metrics. This will benefit patients with breathlessness and/or low gas transfer and enables natural abundance dissolved 129Xe imaging.