Miralles M, Cairols M, Cotillas J, Giménez A, Santiso A
Servicio de Cirguía Vascular, Departamento de Cirgía, Hospital Universitario del Mar, Barcelona, Spain.
J Vasc Surg. 1996 Mar;23(3):428-35. doi: 10.1016/s0741-5214(96)80007-3.
Our purpose was to assess the accuracy and optimal threshold values of the Doppler parameters of the renal arteries and parenchyma for detecting renal artery stenosis (RAS) greater than 60% and occlusion.
Renal duplex ultrasonography and standard angiographic studies of the renal arteries were performed in 78 patients for comparative analysis. Three degrees of RAS were considered: less than 60%, greater than 60%, and occlusion. The following parameters of the Doppler wave were measured in the signal obtained from the main renal artery and interlobar arteries: peak systolic velocity (PSV), end-diastolic velocity, peripheral resistance index, acceleration time, acceleration index, and renal/aortic ratio (RAR).
Logistic regression analysis identified the PSV in the renal artery as the best parameter to differentiate RAS less than 60% from RAS greater than 60%. Only when this parameter was excluded were the RAR and end-diastolic velocity in the renal artery the variables accepted as the best predictors. Receiver-operator curve analysis revealed a PSV in the main renal artery greater than 198 cm/sec and RAR greater than 3.3 as the best cutoff points for detecting RAS greater than 60%. A PSV above this threshold provided 87.3% sensitivity and 91.5% specificity. The RAR showed similar specificity (92.4% but a much lower sensitivity (76.4%). A kidney length less than 8.5 cm, in addition to an absent Doppler signal in renal parenchyma, was the best criterion to identify renal artery occlusion. On the basis of the above-mentioned criteria, renal duplex scanning correctly identified 86 of 94 cases of RAS less than 60%, 41 of 48 cases of RAS greater than 60%, and six of seven occlusions (kappa value = 0.8).
These results suggest that the PSV in the renal artery is the best predicting Doppler parameter to detect RAS greater than 60%. A PSV greater than 198 cm/sec may be an appropriate cutoff point to diagnose this group of stenosis. The RAR did not add any predicting utility in this series. An absent Doppler signal in the renal parenchyma and a kidney length less than 8.5 cm were the best predictors of renal artery occlusion.
我们的目的是评估肾动脉和肾实质的多普勒参数对于检测大于60%的肾动脉狭窄（RAS）及肾动脉闭塞的准确性和最佳阈值。
对78例患者进行了肾双功超声检查和肾动脉标准血管造影研究以进行对比分析。将肾动脉狭窄分为三度：小于60%、大于60%和闭塞。在从肾主动脉和叶间动脉获取的信号中测量以下多普勒波参数：收缩期峰值速度（PSV）、舒张末期速度、外周阻力指数、加速时间、加速指数以及肾动脉/主动脉比值（RAR）。
逻辑回归分析确定肾动脉中的PSV是区分小于60%的RAS与大于60%的RAS的最佳参数。只有排除该参数后，肾动脉中的RAR和舒张末期速度才被视为最佳预测变量。受试者操作特征曲线分析显示，肾主动脉中PSV大于198 cm/秒和RAR大于3.3是检测大于60%的RAS的最佳截断点。高于此阈值的PSV提供了87.3%的敏感性和91.5%的特异性。RAR显示出相似的特异性（92.4%），但敏感性低得多（76.4%）。肾实质中无多普勒信号且肾长度小于8.5 cm是识别肾动脉闭塞的最佳标准。基于上述标准，肾双功扫描正确识别出94例小于60%的RAS中的86例、48例大于60%的RAS中的41例以及7例闭塞中的6例（kappa值 = 0.8）。
这些结果表明，肾动脉中的PSV是检测大于60%的RAS的最佳预测多普勒参数。PSV大于198 cm/秒可能是诊断这组狭窄的合适截断点。在本系列中，RAR没有增加任何预测效用。肾实质中无多普勒信号和肾长度小于8.5 cm是肾动脉闭塞的最佳预测指标。
