2021 International Conference on Medical Imaging Physics and Engineering and the 10th National Annual Meeting of Medical Imaging Physics (ICMIPE 2021)

The dual-nuclei simultaneous imaging spectrometer is the technical prerequisite for combining dual-nuclei imaging. However, most commercial magnetic resonance image (MRI) spectrometers only support proton (1H) imaging. At present, most multinuclear simultaneous imaging methods are realized by modifying the transceiver chain with an additional frequency synthesizer. One of the serious problems is the differences of the frequency resolution, thermal effects and so forth between the spectrometer’s frequency synthesizer and the external synthesizer. Such schemes will affect the phase coherence between transmitter and receiver of 1H channel. In this work, a digital distributed MRI spectrometer for dual-nuclei simultaneous imaging was developed. Truly synchronous excitation of 1H and phosphorus (31P), segmented spatial encoding, interleaved and synchronous acquisition of 31P and 1H signals were realized. The feasibility and flexibility of dual-nuclei simultaneous imaging had been verified respectively with a modified gradient echo sequence at 4.7 Tesla and a redesigned gradient echo sequence at 3.0 Tesla. The results show that dual-nuclei imaging with equal in-plane resolution can be successfully achieved using the redesigned gradient echo sequence, which further verified the flexibility of the dual-nuclei simultaneous imaging spectrometer. Moreover, the spectrometer can be applied to the combined imaging of any two nuclei, which provides inspiring possibilities for future research and potential preclinical or clinical application.
 

multinuclear,simultaneous,distributed,spectrometer,MRI