相关实验视频
Updated: Jul 17, 2025

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Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
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使用压缩传感和共享速度编码的高度加速的自由呼吸实时2D流量成像.
Fei Xiong1,2, Tilman Emrich2,3,4, U Joseph Schoepf5
1Siemens Medical Solutions USA Inc, Cardiovascular MR R&D, Chicago, IL, USA.
European radiology
|September 2, 2023
概括
压缩感应实时 (CS RT) 相对比MRI准确地测量血流的节奏,而不需要呼吸. 这种技术对于心律失常或呼吸控制不良的患者来说是可行的,与传统方法有很好的一致性.
科学领域:
- 心血管磁力共振成像 (MRI) 的方法
- 流量量化的量化流量.
- 医疗成像医学成像
背景情况:
- 传统的相对照 (PC) MRI 面临着不规则的心跳和呼吸运动的挑战.
- 实时 (RT) PC MRI为准确的流量测量提供了一个有希望的替代方案.
- 需要加速技术来提高RT-PCMRI的时间分辨率.
研究的目的:
- 为了评估一个原型的压缩传感 (CS) 加速的2DRT-PCMRI技术.
- 为了评估共享速度编码 (SVE) 的准确性,用于节拍到节拍的流量测量.
- 为了比较CS RT-PC MRI与传统和完全采样PC序列的性能.
主要方法:
- 实施一个CS RT-PC技术,使用单射速梯度回声与SVE.
- 在1-5次心跳中获得高时间分辨率 (51-56.5毫秒) 的获取.
- 在3TMRI系统上对大动脉剖析幻象 (n=8) 和健康志愿者 (n=7) 进行的研究.
- 使用峰值速度,峰值流速,净流速和最大速度计算进行比较.
- 统计分析包括线性回归,类内相关性 (ICC) 和布兰德-阿尔特曼分析.
主要成果:
- 在幻影研究中,有很好的相关性 (R2 ≥ 0.93) 和一致性 (ICC ≥ 0.97).
- 在健康志愿者中,良好的相关性 (R2 ≥ 0.80) 和一致性 (ICC ≥ 0.90).
- 在CS RT-PC MRI中观察到的最大速度和流速的轻微低估 (~12%) 在志愿者中.
结论:
- 具有SVE的高度加速的CS RT-PC MRI技术可用于在不呼吸的情况下进行节拍对节拍流动评估.
- 原型CS RT-PC技术提供了可靠的流量测量,与传统的PC MRI相提并论.
- 这种自由呼吸技术提供了更好的时间分辨率和图像质量,对心律失常患者有益.
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