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随时接地以减少MRI扫描仪在未屏蔽环境中运行的电磁干扰
Beatrice Lena1, Bart de Vos1, Teresa Guallart-Naval2
1C.J. Gorter MRI Center, Leiden University Medical Center, Leiden, Netherlands.
Magnetic resonance in medicine
|October 24, 2025
概括
在便携式低场MRI扫描中,对象接地有效地减少了电磁干扰 (EMI). 这种简单的技术可显著提高手部成像的图像质量,并与射频屏蔽相结合,可增强大脑成像.
科学领域:
- 医疗成像医学成像
- 生物医学工程 生物医学工程
- 物理 物理学 物理
背景情况:
- 便携式低场MRI提供了点的护理成像优势.
- 电磁干扰 (EMI) 在不受屏蔽的环境中降低了图像质量.
- 有效的EMI缓解对于诊断实用性至关重要.
研究的目的:
- 评估受试者接地作为一种减少便携式低场MRI中EMI的方法.
- 为了比较不同的接地策略的有效性.
- 评估对图像质量和信号噪声比 (SNR) 的影响.
主要方法:
- 实验使用47mT和72mT的MRI扫描仪与轮旋转回声序列.
- 试验对象的接地是通过导电套或ECG电极实现的.
- 在环境,单频和宽带条件下进行了EMI测试.
主要成果:
- 在手和大脑成像中,对象接地显著降低了EMI.
- 导电套件可以将手部成像噪声降低高达85倍.
- 用射频屏蔽接地使脑成像噪声降低到基线的1.2倍,即使添加了EMI.
结论:
- 主体接地是一种简单,有效和可重复的EMI缓解策略,用于低场MRI.
- 它特别有利于手部成像,并补充了用于脑部成像的射频屏蔽.
- 这种方法在各种EMI条件和扫描仪类型中是稳健的.
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