Submillimeter morphologic lung MRI at 0.55T using balanced steady-state free precession with half-radial dual-echo readout (bSTAR)

In this work we explore the potential of free-breathing balanced steady-state free precession half-radial dual-echo imaging technique (bSTAR) for morphologic lung MRI in human subjects using high-performance 0.55T MR-scanner. The technique combines an efficient minimal-TR readout sampling with interleaved wobbling Archimedean spiral pole trajectories and retrospective respiratory self-gating. Lung imaging at 0.55T helped to markedly reduce off-resonance artifacts while providing an improved signal intensity and allowed for high-quality morphologic lung MRI at a submillimeter spatial resolution.