MR相位对比脉冲序列在胸部血管成像中的应用

Application of MR phase-contrast pulse sequence in thorax vasculature

目的 探讨MR相位对比脉冲序列在胸部血管成像中的应用价值。方法 选取正常健康志愿者 10例 ,其中男5例、女 5例 ,应用PhilipsGyroscanNT 1.5T磁共振成像仪 ,采用 2D QF序列在垂直于降主动脉、肺动脉干、上腔静脉和右肺上叶动脉长轴走行的方向上进行单层扫描。结果 通过MR相位对比脉冲序列扫描 ,分别获得各血管的模数图和相位图。模数图中 ,各血管断面为圆形 ,呈现为高信号影 ;相位图中 ,血管内实际血流速度与流速编码方向一致时 ,呈现为亮信号影 ,与流速编码方向相反时 ,呈现为暗信号影。结论 采用MR相位对比脉冲序列扫描 ,不仅可以对较大动脉进行成像 ,而且对于静脉和较细小的动脉亦可获得高质量的图像 。

Objective To investigate the application value of thorax vasculature with MR phase-contrast pulse sequence. Methods Ten healthy volunteers were scanned with 2D/QF sequence by Philips Gyroscan NT 1.5?T MR imager. The single scan slice was perpendicular to the long axis of the descending aorta, the main pulmonary artery, the upper vena cava and the right upper artery. Results Modulus images and phase images were acquired by MR 2D/QF sequence scanning. At modulus images, the vascular cross-sections were round and presented high signal. At phase images, the blood flow showed bright signals when the flow direction was consistent with the velocity-encoded gradient,and presented dark signals when the flow direction was opposite to the direction of velocity-encoded gradient. Conclusion By MR phase-contrast pulse sequence scanning, not only are high quality images of the great arteries acquired, but also those of the veins and small arteries are acquired well. With the help of flow analysis software, hemodynamic study can be performed.