超声造影评估移植肾动脉狭窄程度的应用

Application of contrast-enhanced ultrasound in evaluating the degree of transplant renal artery stenosis

目的评价超声造影在移植肾动脉狭窄(transplant renal artery stenosis,TRAS)程度评估中的临床应用价值及其诊断重度TRAS的诊断效能。方法将复旦大学附属中山医院2013年2月至2022年2月经数字减影血管造影(digital subtraction angiography,DSA)或磁共振血管成像(magnetic resonance angiography,MRA)确诊为TRAS的23例(其中2例为MRA诊断)受者作为研究对象,随机选取同期行肾移植术后血流正常、肾功能稳定的32例受者为对照组,回顾性分析上述55例受者的临床及随访资料。根据DSA或MRA显示的移植肾动脉内径减少率,将上述23例受者又分为重度狭窄组(18例)和轻中度狭窄组(5例)。对上述55例受者的超声造影图像进行定量分析,得出造影定量参数:叶间动脉上升时间(rising time of interlobular artery,RTi)、皮质上升时间(rising time of cortex,RTc)、髓质上升时间(rising time of medulla,RTm)、叶间动脉达峰时间(time to peak of interlobular artery,TTPi)、皮质达峰时间(time to peak of cortex,TTPc)、髓质达峰时间(time to peak of medulla,TTPm)。比较重度狭窄组、轻中度狭窄组及对照组三组间超声造影定量参数的差异,并评估各个超声造影定量参数诊断重度TRAS的诊断效能。结果超声造影定量参数RTi、RTc、TTPi、TTPc在轻中度狭窄组与正常组间差异有统计学意义(均P<0.05),RTi、RTc、RTm、TTPi、TTPc、TTPm在重度狭窄组与对照组间差异均有统计学意义(均P<0.05),RTm在轻中度狭窄组及重度狭窄组间差异有统计学意义(P<0.05)。与对照组相比,轻中度狭窄组受者RTi、RTc、TTPi、TTPc延长,重度狭窄组RTi、RTc、RTm、TTPi、TTPc、TTPm均明显延长(均P<0.05)。重度狭窄组受者RTm较轻中度狭窄组受者延长(P<0.05)。以上各个参数中RTc诊断重度TRAS的诊断效能最佳(AUC=0.848),诊断敏感度、特异度及准确率分别为72.22%、86.49%、81.82%。结论超声造影可以用于评估TRAS受者狭窄程度,在诊断重度TRAS方面有一定的临床应用价值,其中参数RTc诊断重度TRAS的诊断效能最高。

Objective To explore the feasibility of contrast-enhanced ultrasound in assessing the degree of transplant renal artery stenosis(TRAS)and evaluate its diagnostic efficacy of severe TRAS.Methods From February 2013 to February 2022,clinical and follow-up data are retrospectively reviewed for 23 TRAS recipients.A definite diagnosis is made by magnetic resonance angiography(MRA,2 cases)or digital subtraction angiography(DSA,21 cases).They are assigned into two groups of mild-moderate stenosis(5 cases)and severe stenosis(18 cases)according to the diameter reduction rate of transplanted renal artery detected by DSA/MRA.Another 32 recipients of stable renal function are selected as controls.All contrast-enhanced ultrasonic images are quantitatively processed with SonoLiver.The following quantitative parameters are obtained,including rising time of interlobular artery(RTi),rising time of cortex(RTc),rising time of medulla(RTm),time to peak of interlobular artery(TTPi),time to peak of cortex(TTPc)and time to peak of medulla(TTPm).The differences of contrast-enhanced ultrasonic quantitative parameters are compared among three groups.And their diagnostic efficacies are calculated in the diagnosis of severe TRAS.Results As compared with those in normal group,RTi,RTc,TTPi and TTPc are significantly longer in mild-moderate stenosis group(all P<0.05);Meanwhile,RTi,RTc,RTm,TTPi,TTPc and TTPm are significantly longer in severe stenosis group than those in normal group(all P<0.05);Comparing mild-moderate stenosis and severe stenosis groups,only RTm is significantly different between two groups(P<0.05).Among all the above parameters,RTc has the highest diagnostic efficacy in the diagnosis of severe TRAS(AUC=0.848)with a sensitivity of 72.22%,a specificity of 86.49%and an accuracy of 81.82%.Conclusions The quantitative parameters of contrast-enhanced ultrasound offer aid in assessing the degree of TRAS.And RTc is the most valuable in the diagnosis of severe TRAS.