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一个用于高密度接收阵列的线圈通道复合器,与MR-linac兼容
Tom Bosma1, Jan G M Kok1, Pim T S Borman1
1Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
Physics in medicine and biology
|May 2, 2025
概括
一个新的4:1复合器允许在MRI系统中添加更多的频道,从而实现更快的成像. 该设备可靠地分离线圈通道图像,保持灵敏度图,信号噪声比损失最小.
科学领域:
- 医疗成像医学成像
- 电气工程 电气工程
- 生物物理学的生物物理.
背景情况:
- 磁共振成像 (MRI) 系统通常对接收线圈的通道数量有限.
- 将高通道计数线圈改装到现有的模拟读出链上是具有挑战性的.
- 例如,MR-linac系统仅限于每个线圈元件的四个通道.
研究的目的:
- 开发和验证一个原型的附加多重处理器,以增加接收线圈通道数量.
- 为了在具有模拟读出链的系统上使用高通道计数线圈.
- 评估多重复合对图像质量和并行成像性能的影响.
主要方法:
- 一个使用CMOS开关的4:1时间分割多重处理器被设计和实施.
- 在重建后,通过解决基于方形波调制的方程来分离线圈通道图像.
- 该原型在1.5T测试,使用具有图像质量的幻影和生物组织.
主要成果:
- 复合器可靠地分离了线圈通道图像,保存了线圈灵敏度图.
- 道间泄漏低于-30 dB.
- 由于数据压缩,信号与噪声比被减少了每个频道的两倍.
- 平行成像的g因子基本上没有受到影响.
结论:
- 演示了一种用于MRI读出链的功能 4:1卷轴通道附加多重处理器.
- 这项技术预计将为临床MRI系统实现显著的成像加快速度.
- 该解决方案解决了临床系统的局限性,限制了接收线圈通道兼容性.
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