肾动脉高分辨力三维增强磁共振血管成像术:透视触发和并行采集技术使用初探

目的:评估透视触发和并行采集技术用于肾动脉高分辨力三维增强磁共振血管成像术的可行性和对肾动脉的显影诊断效果。方法:90例临床诊断或怀疑肾动脉或腹主动脉病变的患者行高分辨力肾动脉三维增强磁共振血管成像(3D CE MRA)。使用透视触发软件启动肾动脉3D CE MRA扫描,扫描采用K空间中心填充法和加速因子为2的并行采集技术。分析图象质量和病变显示情况,并与其它检查结果对照。结果:肾动脉3D CE MRA显示了90例患者共810支动脉段(100%显示率),平均显示等级为3.88。3D CE MRA显示8例11支副肾动脉,显示等级均为4.0。肾动脉段级分支的显示率为73%(66/90例)。所有病例在动脉显示区静脉均未显影或显影很淡,平均等级为0.20。3D CE MRA发现639支动脉段正常;66支动脉段管壁不规则;55支动脉段轻度狭窄;37支动脉段严重狭窄;2支动脉段闭塞;11支动脉段动脉瘤形成。其中96支肾动脉存在狭窄,11支副肾动脉均正常。共有43例病例,肾动脉3D CE MRA与其它血管成像技术作了比较,3D CE MRA的检查结果与之完全符合。结论:透视触发并行采集肾动脉高分辨力3D CE MRA简单可行,成像时间短,空间分辨力高,能清楚显示肾动脉且无静脉污染。

High-Resolution 3D Contrast-Enhanced MR Angiography of the Reanl Arteries with Fluoroscopic Triggering and Parallel Acquisition Techniques:Preliminary Experience

Objective:To evaluate the feasibility and diagnostic capability of renal arteriography using high resolution 3D contrast enhanced MR angiography with fluoroscopic triggering and parallel acquisition techniques.(Methods:)Ninety(patients) with clinically diagnosed or suspected renal artery or abdominal artery diseases underwent high-resolution 3D contrast-enhanced MR renal arteriography(3D CE MRA).Fluoroscopic triggering technique was used to trigger 3D CE MRA of the renal arteries.The techniques,including elliptical centric view order for filling the k space and parallel acquisition technique with an acceleration factor of 2,were used in 3D CE MRA.The overall image quality and demonstration of vascular pathology were studied.3D CE MRA findings were also compared with those acquired by other imaging modalities if (available.)Results:3D CE MRA identified all 810 arterial segments in all subjects(100%) with a mean visibility score of(3.88.)3D CE MRA additionally showed 11 accessory renal arteries in 8 patients.The depiction rate of segmental renal arteries was 73%(66/90).Venous contamination was rated as none or minimal,with a mean score of 0.20.The results showed 639 normal arterial segments and 171 pathological arterial segments,the latter including 66 segments with irregularity;55 segments with mild stenosis;37 segments with significant stenosis;2 segments with occlusion and 11 segments with aneurysms.3D CE MRA identified stenosis involving 96 renal arteries.All accessory renal arteries were normal.On the arteriograms acquired with other imaging techniques of the 43 available cases,the vascular pathological findings were all consistent with those shown on 3D CE MRA arteriograms.Conclusion:High resolution 3D CE MRA of the renal arteries with fluoroscopic triggering and parallel acquisition techniques was feasible and easy to manage.Potentials,including reduction of scanning time,improvement of spatial resolution as well as clear and optimal depiction of renal arteries without venous contamination could be provided by this 3D CE MRA technique.