Bulumulla S B, Fiveland E, Park K J, Foo T K, Hardy C J
GE Global Research, 1 Research Circle, K1-3C12A, Niskayuna, NY 12309.
GE Global Research, 1 Research Circle, K1-3C12A, Niskayuna, NY 12309.
Magn Reson Imaging. 2015 Apr;33(3):351-7. doi: 10.1016/j.mri.2014.12.004. Epub 2014 Dec 16.
As the number of coils increases in multi-channel MRI receiver-coil arrays, RF cables and connectors become increasingly bulky and heavy, degrading patient comfort and slowing workflow. Inductive coupling of signals provides an attractive "wireless" approach, with the potential to reduce coil weight and cost while simplifying patient setup. In this work, multi-channel inductively coupled anterior arrays were developed and characterized for 1.5T imaging. These comprised MR receiver coils inductively (or "wirelessly") linked to secondary or "sniffer" coils whose outputs were transmitted via preamps to the MR system cabinet. The induced currents in the imaging coils were blocked by passive diode circuits during RF transmit. The imaging arrays were totally passive, obviating the need to deliver power to the coils, and providing lightweight, untethered signal reception with easily positioned coils. Single-shot fast spin echo images were acquired from 5 volunteers using a 7-element inductively coupled coil array and a conventionally cabled 7-element coil array of identical geometry, with the inductively-coupled array showing a relative signal-to-noise ratio of 0.86 +/- 0.07. The concept was extended to a larger 9-element coil array to demonstrate the effect of coil element size on signal transfer and RF-transmit blocking.
随着多通道MRI接收线圈阵列中线圈数量的增加，射频电缆和连接器变得越来越笨重，这降低了患者的舒适度并减缓了工作流程。信号的电感耦合提供了一种有吸引力的“无线”方法，有可能减轻线圈重量和成本，同时简化患者设置。在这项工作中，开发了用于1.5T成像的多通道电感耦合前部阵列并对其进行了表征。这些阵列包括与次级或“嗅探”线圈电感式（或“无线”）链接的MR接收线圈，其输出通过前置放大器传输到MR系统机柜。在射频发射期间，成像线圈中的感应电流被无源二极管电路阻断。成像阵列完全无源，无需向线圈供电，并通过易于定位的线圈提供轻量级、无束缚的信号接收。使用7元素电感耦合线圈阵列和几何形状相同的传统有线7元素线圈阵列从5名志愿者身上采集了单次快速自旋回波图像，电感耦合阵列的相对信噪比为0.86±0.07。该概念被扩展到更大的9元素线圈阵列，以证明线圈元件尺寸对信号传输和射频发射阻断的影响。
