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同轴双极阵列具有切换传输灵敏度,用于超高场MRI.

Dario Bosch1,2,3, Georgiy A Solomakha1, Felix Glang1,4

  • 1Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.

Magnetic resonance in medicine
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PubMed
概括

研究人员开发了可重新配置的双极天线,用于超高场MRI. 这种新的方法通过电子切换发射场模式来提高翻转角度的均性,从而可能减少对更多发射通道的需求.

关键词:
射频闪光是一种RF-shimming.阵列数组是一个数组.双极体是双极体,它们是双极体.kT-点的时间.pTxx 的意思是

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科学领域:

  • 磁共振成像 (MRI) 是一种磁共振成像技术.
  • 电磁学 电磁学 电磁学 电磁学
  • 天线工程天线工程

背景情况:

  • 在超高射场 (UHF) MRI 中实现均的翻转角度是具有挑战性的,因为B1+场的不均性.
  • 现有的解决方案往往需要复杂的硬件或更多的传输通道.

研究的目的:

  • 为了研究具有电子可切换发射场模式的双极天线.
  • 为了改善超高场MRI的翻转角度均性.

主要方法:

  • 概念化和构建可重构的双极元件,能够产生两个不同的B1+场形状.
  • 将八个元素集成到一个阵列中,使用PIN二极管和电感器调节电流.
  • 通过电磁模拟和9.4TMRI测量评估性能,评估激发脉冲期间的快速切换.

主要成果:

  • 模拟显示,在当前调制下,上级和下级区域之间的B1+场变化约为30%.
  • 快速切换提高了pTx脉冲的翻转角度均度的约2.2倍.
  • 原型阵列显示了一个较弱的~10%的高级-低级B1+变异.

结论:

  • 具有可切换传输灵敏度的同轴双极阵列为设计激发脉冲提供了一种新方法.
  • 这种方法可以提高翻转角度的均性,而不会造成传输通道的昂贵增加.