TR-resolved Real-Time Low-Field CMR using Hermitian Motion Corrected Reconstructions

Motivation: Real-time cardiac MR could provide new insights into function of the myocardium while avoiding artefacts arising from cardiac and/or respiratory motion. Goal(s): High temporal resolution real-time cardiac MR is particularly challenging at low field (0.55T) due reduced SNR and coil elements available on commercial systems. Approach: Here, we leverage motion compensated reconstructions and Hermitian symmetry to enable the highly undersampled reconstructions required for real-time cardiac MR at low field. Results: Experiments at 0.55T show that the proposed approach enables imaging with a temporal resolution of 6 ms (R~48x) with minimal aliasing, outperforming conventional compressed sensing (considerable aliasing) and parallel imaging (aliasing dominated). Impact: TR-resolved (6ms temporal resolution) real-time cardiac is demonstrated at 0.55T where SNR is limited. Such highly accelerated imaging may reveal finer details in myocardial function. Additionally, the high acceleration factors achieved here could also be leveraged for 3D real-time imaging.