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宽带接收线圈阵列设计,使用高阻抗放大器进行宽带解
Chenhao Sun1,2, Courtney C Bauer1, Jue Hou1
1Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas, USA.
Magnetic resonance in medicine
|June 29, 2023
概括
一种新方法简化了多核MRI/S线圈设计,通过使用单个预放大器进行宽带解. 这种方法提高了多个核的成像速度和信号噪声比 (SNR).
科学领域:
- 磁共振成像是一种磁共振成像技术.
- 线圈工程 线圈工程
- 核磁共振光谱学 核磁共振光谱学
背景情况:
- 多核MRI/S正在获得引力,但目前的线圈设计复杂,需要多个预放大器和不同核的脱电路.
- 对于多核接收阵列线圈的现有方法涉及嵌套单调线圈或使用复杂的切换元件,从而增加多个通道或核的复杂性.
研究的目的:
- 引入多核阵列线圈的新型线圈脱机制,简化硬件要求.
- 为了使用单一套预放大器实现宽带脱,减少多核MRI/S系统的复杂性.
主要方法:
- 使用高输入阻抗预放大器来实现宽带脱,取代了传统的隔离预放大器.
- 一个多调匹配网络 (电感器-电容器-电容器) 和一个电线变压器被用来连接表面线圈与高阻抗前放大器.
- 拟议的配置是对传统预放大器脱方法进行测试的板和扫描仪.
主要成果:
- 这种新的方法在25MHz带宽中实现了超过15dB的脱,覆盖23Na和2H的Larmor频率在4.7T.
- 与传统方法相比,多调的原型显示出61% (2H) 和76% (23Na) 的成像SNR.
- 在较高负载条件下,原型相对于传统配置保持了76% (2H) 和89% (23Na) 的SNR.
结论:
- 本文介绍了一种简化的方法,用于构建高元素数的多核阵列线圈.
- 拟议的技术可以通过单一层阵列线圈和预放大器实现宽带脱.
- 该方法可促进加速成像和改善SNR在多核MRI/S应用中.
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