《国际循环》：肾血管性高血压的无创性筛查手段包括核磁共振血管造影、计算机断层扫描血管造影、多普勒超声和卡托普利肾动态显像。对于上述检查手段的选择，您有哪些建议？

    <International Circulation>: The non-invasive screening techniques for renovascular hypertension include MR angiography， CT angiography， Doppler ultrasound and captopril renal scintigraphy. Do you have any advice on how physicians should choose these techniques?

     Lerman教授：有些研究比较了上述不同方法的敏感性和特异性。我所在的医院采用几种影像学技术来发现和评价肾动脉狭窄的解剖学和血流动力学变化。肾动脉狭窄可导致肾血管性高血压。我们一直在应用核磁共振（MR）血管造影，但是由于造影中使用的对比剂钆会导致肾源性系统性硬化症（nephrogenic systemic fibrosis，NSF）的发生，因而在肾功能受损的患者中，MR血管造影的应用有所减少。相比之下，计算机断层扫描（CT）血管造影的应用增加。在20世纪80年代和90年代，卡托普利肾动态显像得到了广泛应用，但是目前用得要少一些。多普勒超声是一种花费低廉的无创性技术，很多地方都能开展。多普勒超声能评价血流速度和压力波形，但是其效果取决于操作者。我们采用多普勒超声评价了肾动脉狭窄处的血流速度（正常动脉的平均血流速度为100 cm/s），收缩期峰值速度>180~200 cm/s 即被认为存在显著的肾动脉狭窄（定义为动脉直径缩小60%以上）。这些都是目前常用的检测手段。但是，动脉内血管造影和肾静脉肾素水平测定依然是诊断肾血管疾病的“金标准”。

Prof. Lerman: There are a number of studies that compare the sensitivity and specificity of different imaging techniques. In our institution we use magnetic resonance angiography very often. Also， especially with the recent advent of systemic and nephrotic fibrosis that has been observed now the use of MR angiography has decreased a little so we also use CT angiography quite frequently. These are the tests that we currently use most frequently to detect renal artery stenosis. The use of captopril was very popular in the 1980s and 1990s but it has fallen out of favor somewhat and is less common now. The resistive index is also a method that is used but it is operator dependant to a large degree. We use Doppler to measure the velocity of the stenosis of the renal artery and above 2~300 is considered significant. These are all the most popular methods at the moment.