Proton-Frequency-Transparent Coaxial RF coil for X-Nuclei MRI/MRS

Motivation: In multinuclear MRI/MRS, non-proton (X-) coil can interfere with proton (1H) coil, necessitating a solution to prevent their crosstalk. Goal(s): The aim is to create a coaxial X-nuclei coil that is transparent at the 1H frequency, reducing interference and enhancing imaging performance. Approach: The design employs a quarter-wavelength short-ended transmission line stub in a coaxial configuration to avoid additional lumped components and meanwhile ensure 1H transparency. Results: Tests showed the 1H-transparent coaxial X-nuclei coil has a higher unloaded Q factor than LC-trap-based X-nuclei coils, indicating reduced coil loss and enhanced SNR. Impact: This coil design offers a practical solution for X-nuclei MRI by maintaining high impedance at the 1H frequency, reducing interference with proton imaging, and supporting flexible, high-SNR, multinuclear imaging in a compact form.