Liu, C.; Liang, H.; Lu, M.; Gore, J.C.; Sengupta, S.; Yan, X. “Radiofrequency-transparent local B0 shimming coils using float traps.” Magnetic Resonance in Medicine, 2024, DOI: 10.1002/mrm.30361.
In high-field MRI, uneven magnetic fields (B0 inhomogeneities) can lead to poor image quality. A technique called multicoil shimming uses small coils to correct this issue, but traditional coils can interfere with the MRI’s radiofrequency (RF) signals, further reducing image quality. To solve this, a new type of coil has been developed that fixes the magnetic field problem without disrupting the RF signals. The design includes special features that prevent interference, allowing the coil to be placed near the MRI’s main coils without causing issues. Tests showed that this new coil improves magnetic field uniformity, particularly near metal implants, and reduces image distortion while maintaining the quality of the MRI signal. This innovation could enhance MRI scans without requiring major changes to existing equipment.
F I G U R E 1
Design and construction of the transparent direct-current (DC) coil. (A) Schematic diagram of the terminated capacitor configuration, showing the shorted and terminated capacitors of the balun. This figure demonstrates a float balun with the terminated capacitors positioned at one end. Note that they could be terminated at both ends or in the middle. (B) Cross-sectional view of the balun illustrating the placement of copper foil and multi-turn wires. (C) Schematic of the complete coil design, including multiturn wires for DC current and float radiofrequency (RF) baluns. (D) Photograph of a single float RF balun. (E) Another view of the float RF balun demonstrating its capacitor soldering. (F) Top view of the normal DC coil in a square shape, showing the coil configuration and copper wire layout. (G) Top view of the transparent DC coil, highlighting the arrangement of the float RF baluns and multiturn wires. ID, inner diameter; OD, outer diameter.