时间分辨回波分享MRA和并行采集技术的临床应用

目的:评估时间分辨回波分享磁共振血管成像(TREAT MRA)和并行采集技术在血管性病变中的显示效果和临床应用价值。方法:25个临床诊断或怀疑血管性病变患者行TREAT MRA检查,采用3D FLASH序列,用加速因子为2的并行采集技术和回波分享技术填充K空间,采集1帧3D图像用时2~3 s,共12帧动态显示靶血管解剖结构。分析全部病例的图像质量和病变显示情况,并与其它检查作对照。结果:所有病例均顺利完成TREAT MRA检查;TREATMRA动态显示了动静脉充盈情况,至少有1~3帧动脉显示时无静脉污染;所有病例动脉结构显示清楚,包括动脉主干和肾、肺、手足动脉远端分支。TREAT MRA发现2例颈动脉和1例肾动脉狭窄,2例主动脉夹层和破口,前臂血管瘤,足部动静脉瘘和肺动静脉瘘各1例,病变显示清楚,10例行TREAT MRA的病例与其它检查技术结果比较,均与之完全符合。结论:TREAT MRA结合并行采集能以高时间分辨力清楚显示血管结构,效果类似于DSA。

Clinical Application of Time-Resolved Echo-Shared MRA with Parallel Acquisition Techniques

Objective:To evaluate the diagnostic value of time-resolved echo-shared MRA with parallel acquisition techniques.Methods:Twenty-five patients with clinically diagnosed or suspected vascular diseases underwent time-resolved echo-shared MRA(TREAT MRA).A 3D FLASH pulse sequence was used for imaging.This was combined with parallel imaging with an acceleration factor of 2 and echo sharing to reduce the acquisition time to 2~3 seconds per 3D frame.The acquisition was repeated 12 times to depict the arterio-venous anatomy dynamically.The overall image quality and the(demonstration) of vascular pathology were analyzed.TREAT MRA findings were also compared to other imaging modalities if available.Results:TREAT MRA was successfully performed in all patients.It demonstrated dynamically the(arterio)-venous structures.There were at least 1~3 3D frames which depict the arteries without contamination of veins.It clearly(identified) arteries including the distal segments of renal,pulmonary,hand and foot arteries.TREAT MRA detected 2 cases of carotid artery stenosis,1 case of renal artery stenosis,2 cases of aortic dissection,1 case of forearm angioma,1 case of foot arterio-venous fistula and another case of pulmonary arterio-venous fistula.The vascular pathology in these cases was demonstrated clearly.In 10 cases with other imaging techniques available,the demonstration of vascular pathology all agreed to that done by TREAT MRA.Conclusion:TREAT MRA can produce detailed images with high temporal resolution.It has an effect quite similar to DSA.It will play an important role in the diagnosis of vascular pathology.