Reproducibility of pulsed Doppler measurements of the maternal renal circulation in normal pregnancies and those with pregnancy-induced hypertension.

OBJECTIVE: To assess the inter- and intraobserver reproducibilities of pulsed Doppler measurements of the maternal renal circulation in normal pregnancies and those affected by pregnancy-induced hypertension. MATERIALS AND METHODS: Color and pulsed Doppler ultrasound was used to measure acceleration time and resistance index in the renal segmental and interlobar arteries. For the investigation of interobserver reproducibility, two sonographers performed measurements blindly in six normal pregnant women and 14 women with pregnancy-induced hypertension between 28 and 36 weeks' gestation. A second group of 10 patients between 30 and 35 weeks' gestation were examined by one sonographer to assess the level of intraobserver reproducibility of measurements. For each patient in this group, the flow waveform was measured three times in succession. Calculations of the intraclass correlation coefficient Ri were used to determine the level of reproducibility. RESULTS: The interobserver Ri and intraobserver Ri for acceleration time in the segmental artery were 0.95 and 0.96 and for the interlobar artery they were 0.97 and 0.98, respectively. For the resistance index, these values were 0.01 and 0.01 in the segmental artery and 0.52 and 0.29 in the interlobar artery. CONCLUSION: Both the inter- and intraobserver reproducibility of acceleration time measurements in the renal segmental and interlobar arteries were clinically acceptable but the equivalent reproducibilities of resistance index measurements were poor.     

The minimum number of cardiac cycles necessary for calculation of renal blood flow velocity indices in pregnant and non-pregnant women.

In this study Doppler ultrasound was used to measure the blood flow velocity in the main and segmental renal arteries in 16 healthy non-pregnant women. There were no differences in blood flow indices between the right and left kidneys as well as between the main and segmental arteries. The variability of the indices in the main and segmental renal arteries in healthy non-pregnant and in the segmental renal artery in normal pregnant women (32-37 weeks of gestation) was investigated. The within-patient error standard deviations of ten cycles and two, and three to nine averaged cycles were compared. In non-pregnant women, values for the error standard deviation comparable with those obtained from ten cycles for the systolic/diastolic ratio and pulsatility index from both main and segmental arteries were obtained by averaging from five to six consecutive cycles, while the error standard deviation for the resistance index stabilized when averaging only two to four cycles. In pregnant women, the error standard deviations for both the systolic/diastolic ratio and pulsatility index reached quite stable values after three cycle had been averaged as did the error standard deviation for the resistance index. We speculate that this difference between non-pregnant and pregnant women is due to more favorable conditions for renal visualization and consequently higher quality Doppler signals during pregnancy. A knowledge about the number of cardiac cycles required for an accurate calculation of renal blood flow velocity indices may prevent time-consuming calculations and inaccurate conclusions.     

Renal artery stenosis due to fibromuscular dysplasia in a transplanted kidney from a deceased donor: A difficult diagnosis at color doppler ultrasonography

Atherosclerotic renal artery stenosis is a frequent cause of arterial hypertension and/or allograft dysfunction after kidney transplantation and is usually located at the iliac artery anastomosis. Fibromuscular dysplasia is a less frequent, nonatherosclerotic, vascular disease, inducing stenosis at the proximal/mid‐distal part of the renal artery. We report the case of a 44‐year‐old woman, in whom serum creatinine concentration increased and arterial hypertension developed 3 months after renal transplantation. Color Doppler ultrasonography showed a low arterial resistance index and prolonged acceleration time in the interlobar arteries, and a significantly increased peak systolic velocity at the mid third of the renal artery, demonstrating hemodynamically significant stenosis. Percutaneous transluminal angioplasty allowed stenosis correction and was followed by creatinine concentration and arterial blood pressure normalization. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42 :116–120, 2014     

Evaluation of severe transplant renal artery stenosis with Doppler sonography

PURPOSE: To evaluate and determine Doppler criteria for predicting a severe transplant renal artery stenosis (80%-99% diameter reduction) and to compare the Doppler findings in patients with end-to-end and end-to-side anastomosis. METHODS: We performed Doppler sonography on 16 consecutive patients with transplant renal artery stenosis (TRAS) confirmed by digital subtraction arteriography (DSA). Fourteen patients had end-to-end anastomosis, and 2 had end-to-side anastomosis. Eleven patients were re-evaluated with color Doppler sonography within 4 days after intervention. Seven Doppler parameters, including the peak systolic velocity (PSV) in the renal, iliac and interlobar artery, Pre-PSV ratio (the ratio of the PSV in the renal artery to that in the iliac artery), Post-PSV ratio (the ratio of the PSV in the renal artery to that in the interlobar arteries, acceleration time and resistance index, were measured. In the patients with severe TRAS the measurements of these parameters were compared before and after successful intervention. RESULTS: In the 16 patients with a single transplanted kidney, arteriography demonstrated 14 main renal arteries with severe stenosis, and 3 renal arteries with moderate stenosis. When using the cutoff values of Post-PSV ratio >13, renal artery PSV >4 m/sec, acceleration time >0.06 second, and resistance index <0.5 for the detection of all 14 severe stenoses, the sensitivities were 100%, 71%, 93%, and 50%, respectively. For assessing all 14 severe stenoses and 12 severe stenoses of end-to-end anastomosis, the cutoff value of Pre-PSV ratio >5 had sensitivities of 86% and 100%, respectively. Pre-PSV ratios in severe stenoses of end-to-end anastomosis (range, 5.1-11.5) were significantly greater than those recorded in severe stenoses of end-to-side anastomosis (range, 2.8-3.1). Statistically significant differences before and after successful intervention were found for all 7 Doppler parameters in the 7 patients with severe stenosis. CONCLUSIONS: An 80%-99% diameter reduction of the renal artery can be diagnosed based on a Post-PSV ratio >13 for patients with either end-to-end or end-to-side anastomosis. A Pre-PSV ratio >5 for patients with end-to-end anastomosis and acceleration time >0.06 second are helpful in the diagnosis of severe TRAS.     

彩色多普勒超声评价兔肾缺血再灌注前后肾动脉血流动力学变化

目的评价兔肾缺血再灌注24h内肾动脉血流动力学变化。方法运用彩色多普勒超声技术分别监测12只成年日本大白兔肾缺血再灌注前、再灌注后2h、8h及24h肾主动脉、段动脉及叶间动脉的血流动力学改变,测定上述动脉收缩期峰值速度（V max）、舒张末期速度（Vd）、时间平均血流速度（T Amax）、搏动指数（PI）及阻力指数（RI）。结果与缺血再灌注前比较,再灌注2h肾主动脉、段动脉及叶间动脉血流动力学变化差异无统计学意义;再灌注8h肾段动脉、叶间动脉RI增高（P〈0．05）;再灌注24h肾主动脉、段动脉及叶间动脉V max升高、RI和PI增高（P〈0．05）。结论彩色多普勒超声是评价兔肾缺血再灌注24h内肾动脉血流动力学改变的有效方法。     

窒息新生儿肾血流动力学变化与窒息程度关系的研究

目的探讨窒息新生儿肾主动脉、段动脉和叶间动脉血流动力学改变与窒息程度的关系,为临床无创性评价肾功能损害提供诊断依据。方法采用彩色多普勒超声技术分别监测窒息新生儿和正常新生儿出生后24h内的肾主动脉、段动脉和叶间动脉血流动力学参数,即收缩期峰值流速（PSV）、舒张末期流速（EDV）和阻力指数（RI）的变化,同时分析上述参数的变化与新生儿窒息程度的关系。结果与正常组比较,窒息组肾主动脉、段动脉和叶间动脉RI增大,PSV和EDV降低（P〈0．05）;同时轻度窒息与重度窒息患儿的PSV、EDV和RI比较,差异均有统计学意义。结论窒息新生儿肾主动脉、段动脉和叶间动脉血流动力学改变,表现为。肾血流灌注不良、RI增高,且在段动脉和叶间动脉处更为显著;窒息程度与肾内三级动脉的PSV和EDV呈负相关（r=-0．54,-0．79,-0．66,-0．79,-0．79,-0．82,P〈0．05）,与RI呈显著正相关关系（r=0．73,0．73,0．80,P〈0．05）,窒息程度越高RI增高越明显。     

双功彩色多普勒超声对原发性高血压左室肥厚肾内动脉血流的评价

目的：应用双功彩色多普勒超声观察原发性高血压继发左室肥厚患者肾内动脉血流动力学的变化。方法：利用ＡＴＬＵＭ－９及ＨＰｓｏｎｏｓ－２５００超声仪检测了同一年龄组３２例正常人和３０例原发性高血压左室肥厚患者肾内动脉（段动脉、叶间动脉）的血流参数—收缩峰速度（Ｖｓｍａｘ）、舒张期最低流速（Ｖｄｍｉｎ）、阻力指数（ＲＩ）和加速度时间（ＡＴ）。结果：原发性高血压左室肥厚肾脏的段动脉和叶间动脉的ＲＩ、ＡＴ均较正常对照组明显增高（Ｐ均＜０．０１）。Ｖｓｍａｘ和Ｖｄｍｉｎ均明显低于对照组（ｐ均＜０．０１）。结论：原发性高血压左室肥厚患者肾内动脉（段动脉、叶间动脉）的收缩期和舒张期血流均处于低流速，肾血管处于高阻力状态。     

肾动脉狭窄超声诊断的研究进展

超声诊断肾动脉狭窄（RAS）依据为主肾动脉狭窄与狭窄远端肾内动脉血流动力学改变,主肾动脉狭窄处主要指标有峰值血流速度流速加快、主肾动脉狭窄处与主动脉峰值速度之比值升高、主肾动脉收缩峰值加速时间延长等,肾内动脉主要指标有收缩期早期加速时间延长,收缩期早期加速度降低,主肾动脉血与肾内动脉流峰值速度之比增大等。超声造影可以改善了肾动脉的血流显像,提高RAS的诊断率。超声检查为诊断RAS提供了新的有效方法,应多种指标联合应用,并结合临床表现分析诊断RAS,提高RAS的诊断率。     

Intrarenal Doppler ultrasonography: which vessel should be investigated?

The aim of our study was to determine whether the site of intrarenal Doppler measurement influences diagnosis of renal artery stenosis. In an experimental test, three sheep with variable degrees of renal artery stenosis were investigated. In each animal, the resistive index from renal segmental arteries correlated better with mean pressure gradient (r = 0.85, 0.71, 0.85) and had lower standard deviation (s = 0.02 to 0.05) than resistive index from interlobar arteries (r = 0.48, 0.54, 0.61) (s = 0.03 to 0.11). In two animals the difference was significant (correlation: P < or = 0.01, P = 0.13, P < or = 0.05; standard deviation: P < or = 0.01, P < or = 0.34, P < or = 0.05). For detecting renal artery stenosis, vessels within the renal sinus should be used for Doppler sampling.     

正常成人上肢动脉彩色多普勒超声测量

目的　应用彩色多普勒超声检查和测量正常上肢动脉 ,以得出上肢动脉的超声正常值。方法　15 3名健康志愿者 3 0 6条上肢动脉 ,每条上肢分 7个节段。测量解剖学和血流动力学参数。结果　获得上肢动脉各节段各参数超声正常值 ,发现上肢动脉从近心至远心段 ,内径减少 ,管壁变薄 ,收缩期峰值流速、收缩期加速度、搏动指数值下降 (P <0 .0 5 ) ;上肢动脉各节段均可表现多种流速曲线形态 ,近心段以双向三峰所占比例大(67%锁骨下动脉段双向三峰 ) ,腋动脉以远段反向峰渐不明显 (4 5 .2 %肱动脉段单向双峰 )。结论　彩色多普勒超声能成功用于检查上肢动脉 ,发现变异和病变。     

妊高征患者脑血流变化观察

应用经颅多普勒超声（ＴＣＤ）检测３５例妊高征患者（观察组）及３０例正常孕妇（对照组）的大脑中动脉（ＭＣＡ）、大脑前动脉（ＡＣＡ）、大脑后动脉（ＰＣＡ）、椎动脉（ＶＡ）、基底动脉（ＢＡ）收缩期血流速度（Ｖｓ）舒张末期血流速度（Ｖｄ）、平均血流速度（Ｖｍ）及搏动指数（ＰＩ）。结果显示：观察组中的中、重度妊高征患者脑动脉Ｖｓ、Ｖｄ均高于对照组（Ｐ＜０．０１），并随病情加重逐渐升高。观察组各条脑动脉的Ｖｍ均显著高于对照组（Ｐ＜０．０１）。观察组各条动脉ＰＩ值均显著低于对照组（Ｐ＜０．００１）。同时观察３６例妊高征患者眼底，仅３例中度及６例重度妊高征患者眼底血管有痉挛表现。说明：ＴＣＤ能检测妊高征患者脑血管痉挛所致血流速度改变，表现为血流速度加快，脑血管舒缩功能降低。ＴＣＤ能早期提供妊高征患者脑血流动力学资料，避免脑血管病危及孕妇安全。因而可作为妊高征患者预防脑血管并发症的监测手段之一。     

粥样硬化性肾动脉狭窄肾内血流参数分析

目的评价肾内叶间动脉彩色多普勒超声参数对动脉粥样硬化性肾动脉狭窄诊断的准确性。方法以肾动脉造影结果为金标准,双盲对照,专人操作,对123例患者共246个肾进行彩色多普勒超声检查。每例患者均测量肾叶间动脉加速时间、加速度、阻力指数。评价肾内彩色多普勒超声参数诊断粥样硬化性肾动脉狭窄的准确性。结果对≥75%动脉粥样硬化性肾动脉狭窄,肾内指标以加速时间为最好,加速度时间>0.07s诊断的敏感性和特异性分别为85.3%及99.0%;加速度次之,频谱显示及测量精确时,加速度<2m/s2诊断的敏感性和特异性分别为82.4%及85.2%。结论肾内动脉彩色多普勒超声参数诊断≥75%粥样硬化性肾动脉狭窄是一种简便可靠的无创检查手段。     

Evaluation of renal artery stenosis with velocity parameters of Doppler sonography.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of velocity parameters for the diagnosis of renal artery stenosis (RAS) with color Doppler sonography and to determine the optimal threshold values for these parameters. METHODS: The study group was composed of 187 renal arteries, which were examined by color Doppler sonography and angiography. Four Doppler parameters, including the peak systolic velocities (PSVs) in the renal and interlobar arteries, the renal-aortic ratio, and the renal-interlobar ratio (RIR), were measured. Receiver operating characteristic curve analysis was performed to determine the optimal parameter. The sensitivity, specificity, and negative and positive predictive values at various threshold values were calculated. RESULTS: Doppler sonographic examination was technically successful in 96% of renal arteries (180/187). The RIR was determined to be the best parameter. With threshold values of RIR greater than 5, PSV greater than 150 cm/s in the renal artery, renal-aortic ratio greater than 2, and PSV less than 25 cm/s in the interlobar artery, the sensitivity values were 88%, 81%, 70%, and 74%, respectively. An RIR greater than 5 and PSV less than 15 cm/s in the interlobar artery provided the optimal combination of parameters, with sensitivity and specificity of 91% and 87%, respectively. CONCLUSIONS: The RIR is the best velocity parameter in the detection of RAS (> or =50%), and its best cutoff is 5. Valuing influencing factors of PSV in the renal artery will help reduce misdiagnosis. The combination of RIR greater than 5 and PSV less than 15 cm/s in the interlobar artery provides the best diagnostic efficiency of RAS.     

慢性肾病的彩色多普勒研究

以彩色多普勒检测３８例慢性肾病患者（７６只肾）和３２例正常对照者（６４只肾）的肾门动脉，叶段动脉，叶间动脉的最大流速和最小流速以及阻力指数，结果发现肾门动脉、叶段动脉及叶间动脉最大流速（Ｖｍａｘ），最小流速（Ｖｍｉｎ），均低于正常对照组（Ｐ＜０．００１），肾门动脉、叶段动脉和叶间动脉阻力指数高于对照组（Ｐ＜０．００５）。同时用二维测量肾脏大小，发现肾脏大小和肾内各段动脉阻力指数呈负相关，与肾内各段动脉最大流速呈正相关。     

超声评价移植肾动脉狭窄介入治疗前后的变化

目的探讨彩色多普勒超声对移植肾动脉狭窄（TRAS）介入治疗术前、术后血流动力学改变的观察价值。方法TRAS组患者14例,肾移植术后临床生化及超声检测正常的30例患者为对照组。超声测量其肾动脉主干、段动脉及叶间动脉的收缩期峰值流速（PSV）、阻力指数（RI）及血流加速时间（AT）,分别计算肾动脉分别与段动脉、叶间动脉PSV比值。结果①与对照组比较,TRAS组肾动脉主干狭窄段PSV增快,叶间动脉PSV及RI减小,AT增加,肾动脉主干分别与段动脉、叶间动脉PSV比值增大,差异均有统计学意义（P〈0．05）。②与介入治疗术前比较,TRAS组术后肾动脉主干PSV减低,叶间动脉PSV增高,段动脉PSV减低,叶间动脉RI增高,肾动脉主干分别与段动脉、叶间动脉的PSV比值减低,差异均有统计学意义（P〈0．05）。结论彩色多普勒超声能监测TRAS介入治疗后肾动脉和肾内小动脉流速变化,是筛选诊断的首选方法。     

Doppler ultrasound examination of the renal artery in healthy women, normotensive pregnant women and in pre-eclampsia.

A combination of real-time linear array ultrasound scanning and pulsed Doppler ultrasonography was used to record blood flow signals from the right renal artery in 17 healthy women, in 15 normotensive pregnant women and in I7 women with pre-eclampsia. The maximum blood velocity waveforms were analyzed for pulsatility index and systolic/diastolic ratio (S/D ratio). As compared with the two healthy groups, in pre-eclamptic women the pulsatility index was slightly lower (p < 0.05), and the systolic/diastolic ratio non-significantly different. These variables were unrelated to mean arterial pressure or the degree of proteinuria. A theory of renal arteriovenous shunts in pre-eclampsia is proposed. Doppler ultrasound examination of the renal artery would seem to be of limited value-for the purpose of monitoring renal vascular pathology in pre-eclampsia.     

超声间接征象在胸主动脉缩窄性疾病诊断中的价值

目的探讨超声间接征象在胸主动脉缩窄性疾病诊断中的价值及评价重要侧支代偿途径的可行性。方法记录15例胸主动脉缩窄患者腹主动脉、股动脉、肾内叶间动脉、腹壁上下动脉、胸廓内动脉的多普勒频谱;同时选择正常对照组15例,测量正常对照组和胸主动脉缩窄组胸廓内动脉内径和峰值血流速度。结果所用病例腹主动脉、股动脉、肾内叶间动脉均为狭窄下游血流频谱改变,利用血流动力学的异常表现间接推断出胸主动脉缩窄的诊断,最后经手术证实为胸主动脉缩窄。所有病例腹壁上下动脉异常增宽吻合。胸廓内动脉和腹壁下动脉内径异常增宽,峰值血流速度增快,与正常对照组比较,均具有显著性差异（P〈0.01）。结论准确掌握胸主动脉缩窄性疾病的一些重要的间接征象可提高对这类疾病的全面认识。     

彩色多普勒超声联合超声造影对移植肾动脉狭窄的诊断价值

目的:探讨彩色多普勒超声(color Doppler ultrasonography, CDUS)血流动力学参数联合超声造影(contrast-enhanced ultrasound, CEUS)定量参数对移植肾动脉狭窄(transplant renal artery stenosis, TRAS)的诊断价值。方法:分析2011年9月至2020年5月在复旦大学附属中山医院经DSA或MRA确诊的TRAS患者21例(狭窄组)及同期行肾移植且随访肾功能正常的患者37例(对照组)的CDUS及CEUS资料,比较2组CDUS血流动力学参数[主肾动脉收缩期峰值流速(PSV)、峰值流速后比、叶间动脉阻力指数(RI)]及CEUS定量参数[皮质感兴趣区上升时间(RT)、髓质RT、皮质达峰时间(TTP)、髓质TTP]的差异,分析上述各个参数与TRAS程度间的相关性,并通过ROC曲线分析上述参数单独及联合应用时诊断TRAS的效能。结果:狭窄组主肾动脉PSV、峰值流速后比、皮质RT、髓质RT、皮质TTP及髓质TTP的值均高于或长于对照组,叶间动脉RI低于对照组(P0.05);主肾动脉PSV、叶间动脉RI、峰值流速后比、皮质RT、髓质RT、皮质TTP、髓质TTP与TRAS程度均存在中度相关性(r值分别为0.617、-0.409、0.599、0.600、0.518、0.638、0.648),其中叶间动脉RI与狭窄程度负相关,其余超声参数与狭窄程度正相关(P0.05)。CDUS血流动力学参数总体灵敏度高于CEUS定量参数,总体特异度低于CEUS定量参数;CEUS定量参数(除髓质RT外)的曲线下面积普遍大于CDUS血流动力学参数。主肾动脉PSV2.43 m/s及皮质TTP9.26 s是诊断TRAS的重要参数(P0.05),两者联合诊断TRAS的AUC为0.965、准确度为91.40%,高于所有单一参数。结论:CDUS及CEUS均可用于诊断TRAS,CDUS血流动力学参数联合CEUS定量参数可提高TRAS诊断的准确度,从而在一定程度上减少CDUS疑诊病例不必要的放射性检查。     

尸肾移植术后肾功能延迟恢复不同病因的超声诊断

目的：探讨尸肾移植后肾功能延迟恢复不同病因的超声表现。方法：总结分析３７例病因不同、诊断明确的移植肾功能延迟恢复（ＤＧＦ）患者的彩色多普勒超声资料,并与３０例肾移植后肾功能及时恢复者对照。结果：（１）ＤＧＦ者的主肾动脉、段动脉的峰速度、加速度、阻力指数均明显增加（Ｐ＜０．０５、Ｐ＜０．０１）;（２）急性排异者峰速度与舒张期速度的差值较大,其差值占峰速度的７８％以上,肾后梗阻者叶间动脉频谱呈“锯齿”状,阻力指数均小于０．５５;（３）急性肾小管坏死者肾皮质彩色血流信号相对稀少,肾髓质内示多条动静脉短路花色血流信号;急性排异者肾叶间动脉及弓形动脉血流信号不连续脉冲性花色血流信号间存在血流信号的中断;肾后性梗阻者叶间动脉似“脉冲型静脉血流”收缩期与舒张期血流信号的色彩变化较小。结论：应用彩色多普勒超声可辨别引起ＤＧＦ的三种常见病因。     

Doppler blood flow velocity waveforms in the fetal renal arteries: variability at proximal and distal sites in the right and left arteries.

OBJECTIVE: To investigate variability in pulsatility/resistance indices and absolute velocities of blood flow in fetal renal arteries dependent on side and sampling site within each vessel. METHODS: Doppler blood flow measurements of pulsatility index (PI), resistance index (RI) and peak systolic velocity (PSV) and end-diastolic velocity (EDV) were performed in the renal arteries of 27 fetuses between 236 and 247 days of gestation. Velocity waveforms were sampled in both the right and left renal arteries at two different sites: proximally, close to the aorta, and distally, before any major visible bifurcation of the vessels. The intraobserver variation was measured in 15 additional fetuses. RESULTS: Mean values of PI and RI were similar in the right and left renal arteries and at the proximal and distal sampling sites of these arteries. Mean PSV and EDV were higher at the proximal compared to the distal site on both sides. For all parameters the 95% limits of agreement between measurements made in the right and left arteries and at proximal and distal sites were wide but tended to be narrower for the left renal artery and at the distal site. Intraclass correlation coefficients for intraobserver variability were 0.88, 0.89, 0.83 and 0.81 for PI, RI, PSV and EDV, respectively. CONCLUSIONS: It is important to standardize the precise site at which Doppler blood flow velocity waveform measurements are made in the renal arteries of the fetus. On the basis of our observations, we suggest that the left renal artery is the preferred vessel for sampling and that measurements should be made in the renal arterial trunk away from the aorta and before any visible branches.