对螺旋和旋流的2D流MRI的验证
Zia Mehmood1, Hosamadin Assadi1,2, Ciaran Grafton-Clarke1,3
1Norfolk and Norwich University Hospitals NHS Foundation Trust, Norwich, UK.
Open heart
|March 8, 2024
概括
新的二维 (2D) 阶段对比 (PC) 方法可以量化大动脉根中血液流动的螺旋性和旋转性. 这些经过验证的成像生物标志物在临床使用中具有很高的可重复性.
科学领域:
- 心血管成像 - 心血管成像
- 生物医学工程 生物医学工程
- 流体动力学 流体动力学
背景情况:
- 量化大动脉根中的血液流动动力学对于了解心血管健康至关重要.
- 现有的方法在评估复杂的流动模式,如螺旋和旋流等方面可能存在局限性.
研究的目的:
- 开发和验证二维 (2D) 阶段对比 (PC) 磁共振成像 (MRI) 方法来量化大动脉根中的血流螺旋性和旋转性.
主要方法:
- 利用了来自健康对照组和心力衰竭患者的四维 (4D) 流动心血管MRI数据,其中包括保留喷射分数或大动脉狭窄的患者.
- 调整4D流量数据以模拟2DPC平面,量化流量位移 (FD),缩流量逆转比 (sFRR) 和旋转角度 (RA).
- 通过对流向量和定量指标的视觉分析来评估螺旋性和旋转性.
主要成果:
- sFRR在识别流中表现出高精度 (AUC=0.955),值>8%,显示82%的灵敏度和100%的特异性.
- 平均晚期缩FD (流异心标记) 也显示了流检测的显著准确性 (AUC=0.909).
- 定量指标 (FD,sFRR,ΔsRA) 显示出极好的可重现性 (ICC>0.92) 和与手动测量有很强的相关性.
结论:
- 开发的2DPC流量成像技术有效量化了大动脉根中的血液流动螺旋性 (ΔRA) 和旋转性 (FRR).
- 这些新的流动螺旋性和旋转性的成像生物标志物显示出高可重复性,支持潜在的临床采用.
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