协轴单极天线:用于超高场发射/接收阵列的灵活的终端供应天线
Lyanne M I Budé1,2, Bart R Steensma3, Irena Zivkovic2
1Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
Magnetic resonance in medicine
|February 20, 2024
概括
一个新的灵活的同轴单极天线可以在7特斯拉 (7T) 时改善身体成像. 这种设计简化了电缆路由,并显示了前列腺成像的强大性能,提供高B1+字段水平.
科学领域:
- * 磁共振成像 (MRI) 的使用.
- *天线工程 *天线工程
- * 生物医学工程 * 生物医学工程
背景情况:
- * 7特斯拉 (7T) 的高场MRI需要先进的天线设计以获得最佳性能.
- *现有的天线设计可能会受到电缆-线圈合和复杂的路由的影响.
- *对象负载和天线灵活性是有效的身体成像的关键因素.
研究的目的:
- *为7T身体成像引入一种新的同轴单极天线.
- * 用B1+场生成和效率来评估其性能.
- * 评估其适用于前列腺成像应用的适用性.
主要方法:
- *使用有限差异时间域 (FDTD) 方法进行设计和模拟.
- * 幻影测量以确定B1+效率和S参数.
- *使用八通道阵列进行体内前列腺成像.
主要成果:
- *最佳天线长度为360毫米,间隙位置为40毫米.
- * 与分离双极天线相比,B1+水平较高 (20%在前列腺中).
- * 实现了强大的S11性能和高质量的体内前列腺图像,具有10-14μT B1+水平.
结论:
- *同轴单极天线是7T身体成像的灵活和新的设计.
- *简化电缆路由和匹配是主要优势.
- *天线提供与现有设计相匹配的性能,具有改善B1+场生成的潜力.
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