Department of Nanophotonics and Metamaterials, ITMO University, 197101, St. Petersburg, Russia.
Commissariat à L'Energie Atomique et aux Energies Alternatives/Direction de la Recherche Fondamentale/Institut Joliot/Neurospin, 91191, Gif-sur-Yvette Cedex, France.
Sci Rep. 2018 Jun 15;8(1):9190. doi: 10.1038/s41598-018-27327-y.
In this paper, we propose, design and test a new dual-nuclei RF-coil inspired by wire metamaterial structures. The coil operates as a result of resonant excitation of hybridized eigenmodes in multimode flat periodic structures comprising several coupled thin metal strips. It was shown that the field distribution of the coil (i.e. penetration depth) can be controlled independently at two different Larmor frequencies by selecting a proper eigenmode in each of two mutually orthogonal periodic structures. The proposed coil requires no lumped capacitors to be tuned and matched. In order to demonstrate the performance of the new design, an experimental preclinical coil for F/H imaging of small animals at 7.05T was engineered and tested on a homogeneous liquid phantom and in-vivo. The results demonstrate that the coil was both well tuned and matched at two Larmor frequencies and allowed image acquisition at both nuclei. In an in-vivo experiment, it was shown that without retuning the setup it was subsequently possible to obtain anatomical H images of a mouse under anesthesia with F images of a tiny tube filled with a fluorine-containing liquid and attached to the body of the mouse.
在本文中，我们提出、设计并测试了一种新的双核射频线圈，该线圈的设计灵感来自于金属丝超材料结构。该线圈通过多模平板周期结构中几个耦合的薄金属条的混合本征模的共振激励来工作。结果表明，通过在两个相互正交的周期结构中选择适当的本征模，可以独立地控制线圈的场分布（即穿透深度）在两个不同的拉莫尔频率处。所提出的线圈不需要集总电容器进行调谐和匹配。为了演示新设计的性能，我们设计并测试了一个用于在 7.05T 下对小动物进行 F/H 成像的实验性临床前线圈，该线圈在均匀液体体模和体内进行了测试。结果表明，该线圈在两个拉莫尔频率处都调谐和匹配良好，并允许在两个核进行图像采集。在体内实验中，结果表明，无需重新调谐设置，随后可以在麻醉的小鼠上获得包含含氟液体的微小管的 F 图像，并将其附在小鼠的身体上，同时获得小鼠的解剖 H 图像。
