利用4D-Flow技术定量分析肺动脉血流和相对压力的可重复性研究

Reproducibility of Pulmonary Artery Flow and Pressure Difference Measurements Using 4D-Flow MRI

目的肺动脉血流动力学参数的无创测量,对于肺动脉高压的诊断、预后评估和跟踪研究有重要意义。本文主要基于4D-Flow技术对肺动脉血流定量测量和相对压力计算的可重复性进行研究。资料与方法对8例健康志愿者1周内进行2次独立的肺动脉4D-Flow成像,在肺动脉干、左肺动脉和右肺动脉取3个截面,定量分析每个截面的最大流速、每搏输出量、最大流量和平均相对压力等参数,分析各参数的相关性和可重复性。结果利用2次扫描结果成功测量了肺动脉最大流速、每搏输出量、最大流量和平均相对压力,2次扫描结果相关性较好(r=0.880、0.988、0.958、0.953,P<0.001)。Bland-Altman分析结果表明,最大流速、最大流量、每搏输出量和峰值压力结果有较好的可重复性(d=1.30、4.60、1.00、0.04,σd=±8.90、±29.30、±9.20、±0.35)。结论利用4D-Flow技术可以对肺动脉血流及相对压力进行定量分析,并且有较好的可重复性。

Purpose to investigate the reproducibility of blood flow and pressure difference measurements for pulmonary artery using 4D-Flow MRI. Materials and Methods Eight healthy volunteers were scanned twice within a week using 4D-Flow MRI for pulmonary artery segment. Three 2D cross-sectional views including main pulmonary artery, right pulmonary artery and left pulmonary artery were manually chosen to evaluate local hemodynamic parameters such as peak velocity, stroke volume, peak flow and mean pressure difference as well as the reproducibility between two measurements. Results The evaluation of peak velocity, stroke volume, peak flow and mean pressure difference were successfully implemented in all volunteers and a significant correlation between two scans was also found for every measured parameter with correlation coefficients of 0.880, 0.988, 0.958 and 0.953（P〈0.001） respectively. The Bland-Altman results further demonstrated good reproducibility in the measurements for peak velocity, stroke volume, peak flow and mean pressure difference（d=1.30, 4.60, 1.00 and 0.04, σd=±8.90, ±29.30, ±9.20 and ±0.35）. Conclusion Blood flow and PD can be quantitatively measured in pulmonary artery using 4D-Flow MRI with good reproducibility.