三维增强磁共振血管成像在肾动脉造影中的应用

目的 讨论如何提高肾动脉的三维增强磁共振血管成像（3D CE-MRA）的成功机率。方法 33例有高血压病史患者进行3D CE-MRA检查．均采用先行试验性团注造影剂扫描，再采用时间飞跃法血管成像技术作斜冠状位的腹主动脉及肾动脉的3D CE-MRA，通过图像后处理，获得类似于数字减影血管造影的图像。结果 本组病例均得到准确的延迟扫描时间，抓采到造影剂到达肾动脉峰值图像。结论 检查的主要创新在于：采用卵圆中心法扫描（决定图像对比分辨率），而不是按顺序充填K空间；建立信号强度／时间曲线，综合病人年龄、血液循环时间、曲线斜率等以确定延迟扫描时间；择层、择范围、多角度图像重建技术。

Application of three-dimensional contrast-enhanced magnetic resonance angiography in renal artery angiography

Objective To increase the probability of successful renal artery angiography with a three-dimensional contrast-enhanced magnetic resonance angiography(3D CE-MRA).Methods 3D CE-MRA was performed in 33 patients with hypertension.To calculate the scan delay time,a testing contrast agent bolus of 2 ml was injected for single sagital slice real-time scanning,followed by oblique coronal 3D Fast TOF SPGRE.With maximum intensity projection,a set of images was acquired.Results Exact scan delay time was obtained in all the cases from which clear images were acquired with the exception of two cases in which failure of breath-holding occurred during the scanning.Conclusion This examination enhances the performance by adopting elliptical-centric k-space recording for data acquisition for the center in k-space at the beginning of acquisition,and utilizing preceding testing bolus injection and signal intensity/time curve for determining the scan delay time,using slice selection and multiview image reconstruction.