Towards Practical SEMSI at 0.55 Tesla

Motivation: Spectrally-encoded multi-spectral imaging (SEMSI) is an approach for distortion-free MRI around metallic implants, but requires multiple-readouts per TR to be clinically feasible. Goal(s): To determine the benefits of SEMSI over SEMAC at 0.55T, using parameters that are consistent with a future multi-readout SEMSI implementation. Approach: We used single-readout SEMSI to prospectively mimic the performance of multi-readout SEMSI with high slew rate and readout bandwidth. Results: We observe that SEMSI simultaneously achieves the expected SNR improvement and artifacts reduction compared to SEMAC. Impact: SNR improvement is important at 0.55T to examine the tissues near the metallic implants. This prospective study confirms the improvement performance of multi-readout SEMSI which will further improve SNR and scan efficiency.