彩色多普勒超声检测自体肾和移植肾的肾动脉狭窄

目的 探讨彩色多普勒超声在检测自体肾和移植肾肾动脉狭窄(RAS)中的价值和局限性。方法 回顾性对照分析了临床可疑RAS的30例自体肾和14例移植肾的彩色多普勒超声(US)与磁共振动脉造影(MRA)及动脉血管造影的结果。并将狭窄肾动脉扩张／再通术前后的肾动脉血流速度，肾内小动脉多普勒波形特征(升速时间-AT，升速指数-AI，阻力指数-RI)进行了比较。结果 30例自体肾RAS的超声诊断中有2例假阳性和2例假阴性。14例移植肾RAS阳性的超声检查无误差。肾动脉血流速度和肾内小动脉的多普勒波形在RAS纠正术前后有显著改变。结论 尽管彩色多普勒超声在检测RAS中有局限性，其仍被列为对可疑RAS病例的初步影像检查，并在观测随访RAS纠正术后的肾血流灌注及狭窄复发中有重要作用。综合分析肾动脉及肾内动脉的血流速度和多普勒波形特征并参考有关临床资料有助于提高超声诊断RAS的准确性。

Color Duplex Ultrasound in Detecting Renal Artery Stenosis in Native and Transplant Kidneys

Objective To analyze the value and pitfalls of color duplex ultrasound (US) in detecting renal artery stenosis (RAS) in native and transplant kidneys. Methods US results of suspected RAS in 30 native kidneys (17/30 positive and 13/30 negative) and 14 transplant kidneys (14/14 positive) were retrospectively compared with angiography and/or MRA. The renal artery velocity and intrarenal Doppler parameters (acceleration time AT], acceleration index AI], resistive index RI]) were compared pre and post percutaneous transluminal renal artery angioplasty and stent placement (PTRAS). Results There were 2 false positive and 2 false negative US diagnoses of RAS in native kidneys. There was no false US diagnosis of RAS in transplant kidneys. The velocity of renal artery and parameters of the intrarenal arteries were remarkably changed after revascularization. Conclusion Even with its limitations, color duplex ultrasound is still a valuable initial imaging technique for suspected RAS. It is also useful for monitoring arterial reperfusion after correction of RAS. Combining all of quantitative measurements, qualitative Doppler waveform characteristics of the renal artery and intrarenal arteries and related clinical information would help us correctly interpret US study.