实现相一致性:在多隔间系统的平衡稳定状态自由前置MRI中,相描述的重要性
Nils M J Plähn1,2,3, Simone Poli2,3,4, Eva S Peper1,2
1Department of Diagnostic, Interventional and Pediatric Radiology (DIPR), Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
Magnetic resonance in medicine
|February 6, 2024
概括
准确的相位描述对于多分区平衡稳态自由前行 (bSSFP) 信号至关重要. 实验证实了破坏性干扰效应,验证了对bSSFP成像进行预测的模型.
科学领域:
- 磁共振成像技术 磁共振成像技术
- 生物物理学的生物物理.
背景情况:
- 平衡稳态自由前行 (bSSFP) 是磁共振成像 (MRI) 中广泛使用的脉冲序列.
- 对bSSFP信号的准确建模对于定量分析至关重要,特别是在具有多个信号组件的系统中.
研究的目的:
- 为了确定多隔间系统中平衡稳定状态自由前行 (bSSFP) 信号的正确数学阶段描述.
- 解决现有的bSSFP信号模型中关于破坏性干扰效应的差异.
主要方法:
- 根据已发表的模型,为bSSFP信号制定了两个不同的相形容.
- 对水-乙bSSFP信号进行了数值模拟,以评估相位描述预测.
- 在3T的水-乙幻象上使用相循环bSSFP获取进行实验验证.
- 在7T利用局部单声元MRS来确定组件的相对化学转移.
主要成果:
- 模拟的bSSFP配置文件根据所选的阶段描述有显著的差异,显示破坏性干扰的存在或不存在.
- 水-乙混合物的bSSFP实验资料始终显示破坏性干扰.
- 观察到的实验结果验证了理论描述,预测了多间隔系统中的破坏性干扰效应.
- 建立了一种与布洛赫方程一致的方法,用于对多隔间bSSFP信号的正确相位描述进行明确的实验识别.
结论:
- 一致且准确的相位描述对于正确建模多隔间bSSFP信号至关重要.
- 错误的阶段描述导致错误的预测和bSSFP数据的误解.
- 这项研究为了解复杂系统中的bSSFP信号行为提供了经过验证的框架.
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