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Updated: Apr 11, 2026

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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
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一个只有接收的频率转换系统,具有自动相位校正,用于同时进行多核核MRI/MRS
IEEE transactions on bio-medical engineering
|March 5, 2025
概括
本研究介绍了多核核磁共振成像中自动相位校正的硬件解决方案,改进了实时数据采集. 该方法从仅接收的频率转换中纠正相位不一致,从而实现灵活的扫描调整.
科学领域:
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
背景情况:
- 仅接收频率转换允许X核核磁共振扫描仪进行同时/交联的多核实验.
- 这种技术避免了修改传输路径,但由于局部振荡器频率不同而引入相位不一致.
- 目前需要追溯相位校正,限制扫描灵活性.
研究的目的:
- 提出一个硬件解决方案,用于MRI扫描期间的自动实时相位校正.
- 消除在多核收购中需要追溯阶段校正的需要.
- 为了使扫描参数在同时/间隔多核实验中灵活调整.
主要方法:
- 硬件解决方案可以实时检测和纠正局部振荡器 (LO) 的相位变化.
- 实现需要编程备用TTL信号,并访问扫描系统LO.
- 阶段校正应用于传输和接收之间的翻译器LO.
主要成果:
- 硬件解决方案有效地纠正了仅接收频率转换带来的相位不一致.
- 由于相位校正不完善,在31P和23Na频率下观察到大约3%的SNR损失.
- 经过校正的23Na信号显示了8度的相位标准偏差,而参考信号则为6度.
结论:
- 提出的硬件解决方案成功地纠正了多核核磁共振成像中的相位不一致.
- 在相位校正中存在轻微的缺陷,在未来的升级中有可能得到改进.
- 这种方法增强了实时数据采集和扫描参数灵活性,用于多核核磁共振成像.
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