双十字磁墙解用于使用常态差分模式共振器的四度收发器射频阵列线圈
Komlan Payne1, Aditya Ashok Bhosale1, Xiaoliang Zhang2
1Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY 14260, USA.
概括
这项研究引入了一种用于超高场MRI的射频 (RF) 线圈阵列的新型磁性解方法. 该技术有效地抑制了电磁干扰,提高了高级成像应用中的图像质量和安全性.
科学领域:
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 无线电频率 (RF) 工程
- 生物医学工程 生物医学工程
背景情况:
- 与线性极化阵列相比,方位收发器射频线圈阵列提供了更好的信号噪声比 (SNR),空间分辨率和并行成像性能.
- 方形射频线圈中激发功率降低导致特定吸收率 (SAR) 降低,从而提高了患者的安全性.
- 在多通道正方形射频线圈阵列中实现电磁解是具有挑战性的,特别是在超高频场 (UHF),由于复杂的结构和电磁性质.
研究的目的:
- 提出和实施一种新的电磁解方法,用于7特斯拉 (7T) 的多通道方格收发器射频线圈阵列.
- 为了减少多模式电流之间的相互合,使用双交叉磁墙在常态微分模式方程 (CMDM) 阵列中使用双交叉磁墙.
- 为了验证解性能,并评估其对8通道膝盖线圈阵列的场分布和SAR的影响.
主要方法:
- 设计了一种双交叉磁墙脱策略,包括两个内在脱的循环,以最大限度地减少方位收发器射频阵列的相互合.
- 解方法在7T的超高频MRI常态微分模式方位 (CMDM) 方位收发器阵列上实施,用于7T的超高频MRI.
- 进行了数值模拟以研究基于阻抗的脱性能,并使用网络分析仪在与脱网络构建的CMDM阵列上进行了实验性表征.
主要成果:
- 拟议的磁性解墙有效地减少了CMDM阵列中所有多模式电流之间的相互合.
- 分离网络没有与CMDM共振器进行物理连接,为尺寸可调节的射频阵列提供了灵活性.
- 对8通道正方形膝盖线圈阵列的数值模拟显示了压制电流合,并提供了场分布和局部SAR的数据.
结论:
- 双十字磁墙是一种可行且有效的方法,可以在超高电场的多通道方格收发器射频阵列中实现电磁解.
- 这种脱技术通过改善SNR和潜在地减少SAR来提高超高频MRI系统的性能.
- 拟议的方法提供了设计灵活性,并有助于开发用于高性能MRI应用的先进射频线圈阵列.
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