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评估7-T 8 × 2收发器阵列的性能
Junghwan Kim1,2, Changyu Sun1,3, Chan Hong Moon4
1Department of Radiology, University of Missouri, Columbia, Missouri, USA.
NMR in biomedicine
|March 27, 2024
概括
一个新的8x2收发器阵列为7-TMRI提供与商业线圈相比可比的信号噪声比率 (SNR) 和g因子,尽管具有较少的元素. 它的性能强大,能够承受负载变化,显示出出色的大脑成像能力.
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) 线圈设计
- 医学成像技术 医学成像技术
背景情况:
- 分离式收发器阵列对于高场MRI至关重要,但它们相对于仅接收线圈的接收性能仍有争议.
- 由于线圈数量和重叠,现有的收发器设计可能会面临信号噪声比 (SNR) 和并行成像中的g因子方面的挑战.
研究的目的:
- 为了评估7TMRI的8x2无接收器阵列的接收性能.
- 为了比较其噪声相关性,g因子和SNR与商业RF仅接收线圈.
- 为了评估收发器对负载阻抗变化的强度.
主要方法:
- 对8x2收发器阵列和32元商用参考线圈进行比较分析.
- 测量噪声相关性,g因子和SNR在五个人类实验中.
- 在调整/匹配 (TM) 和未调整/未匹配 (UTM) 的负载条件下评估收发器性能.
- 使用T2加权的轮旋转回声序列展示成像性能.
主要成果:
- 8x2收发器阵列实现了与参考线圈相比可比的g因子和SNR,尽管其接收元件数量为半个 (16对32).
- 平均SNR为65±10 (收发器) 和67±15 (参考线圈).
- 噪声相关性对于负载变化是强大的,对于TM和UTM条件的结果是可比的.
- 在T2加权成像过程中,在尾部和面部大脑区域均观察到优异的SNR性能.
结论:
- 分离的8x2收发器阵列显示了对7-T脑MRI的竞争性接收性能.
- 它的设计为传统的仅接收线圈提供了可行的替代方案,提供了强大的SNR和g因子.
- 阵列的性能在不同的负载条件下是可靠的,突出其实际实用性.
关键词:
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