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一系列配对的折叠端二极体,用于9.4 T的全脑成像

K I Popova¹, F Glang², D Bosch³

¹School of Physics and Engineering, ITMO University, St. Petersburg, Russia.

Journal of magnetic resonance (San Diego, Calif. : 1997)

|November 3, 2024

概括

使用配对折叠端二极管的新射频 (RF) 阵列显著提高了B1+场的同质性和9.4T的脑部覆盖. 这种新的设计提供了优越的全脑成像,包括大脑干,与传统的双极阵列相比.

科学领域:

医疗成像医学成像
无线电频率工程无线电频率工程
神经科学是一个神经科学.

背景情况:

实现统一的传输B1+场对于高场MRI至关重要.
现有的射频阵列往往难以保持一致的场均性和覆盖范围,特别是在人脑中.
需要新的天线设计来克服超高场MRI中的这些局限性.

研究的目的:

开发和评估一种新的八元收发器 (TxRx) 阵列,以改善人类头部MRI的传输B1+场均质和纵向覆盖.
为了提高性能,利用基于配对折叠端二极管的复合元件.
为了证明这个阵列在9.4特斯拉 (T) 的可行性,用于全脑成像.

主要方法:

设计了一个八元收发器阵列,使用合的折叠末端二极管,每个通道有一个主动和一个被动合的二极管.
通过调整双极重叠和反应性一次性元素值,数值优化了传输B1+场分布.
在9.4T时从数值和实验上验证了阵列的性能.

主要成果:

拟议的配对折叠式二极管阵列显示了B1+同质性和整个大脑 (包括大脑干) 的纵向覆盖率的显著改善.
与单行折叠末端双极阵列相比,实现了更好的全脑覆盖.
通过使用这个阵列,成功地获得了第一个在9.4T的完整人脑图像,覆盖范围扩展到第四个椎.

结论:

一个新的单行,八元9.4T射频阵列使用配对,被动合的折叠端二极管成功开发和特征.
阵列的设计,采用从主动-被动双极对的横延长场图案,显著改善了传输磁场分布.
这项技术提供了比传统的二极管阵列更好的覆盖范围,使得前所未有的超高场全脑成像成为可能.

关键词:

脑部成像脑部成像双极天线是双极天线.这就是为什么MRI是MRI.无线电射频闪光是一种RF闪光.在UHF,UHF是高频的.

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