Conical readouts for bSSFP at 0.55T

Motivation: To achieve motion-robust, high-resolution imaging on low-field MR systems, efficient k-space sampling is critical. The balanced 3D Cones trajectory improves on this by maintaining a high signal steady-state, optimizing sampling density for high-frequency k-space content. Goal(s): To replace 3D radial signal readout within a free-running framework, enabling time-efficient,high-resolution imaging at low magnetic field strengths. Approach: This work introduces a balanced steady-state free precession sequence with an in-out-in conical trajectory, enhancing time efficiency and k-space sampling. Results: Results demonstrate higher SNR with the conical trajectory compared to Cartesian sequences and sharper images compared to radial sequences, in both in vitro and in vivo experiments. Impact: The 3D Cones trajectory improves sampling efficiency and image sharpness in low-field MR imaging, offering a more effective alternative to Cartesian and radial methods. This advancement enables high-resolution imaging applications, enhancing clinical utility and expanding patient access to diagnostic imaging.