彩超在高血压患者肾动脉血流动力学检测中的应用分析

目的 探讨彩超在原发性高血压患者肾动脉血流动力学检测中的应用价值及临床意义。方法 从我院2014年3月~2016年9月就诊的原发性高血压肾病患者,随机抽取120例为观察组,再随机抽取100例健康人作为对照组,两组均给予肾血管超声检测,根据检测结果数据,分析高血压对肾动脉血流动力学的影响。结果 观察组肾脏的长度、宽度以及肾脏皮质厚度均显著高于对照组;观察组肾脏血流速度（包括峰值流速和最低流速）均低于健康人的对照组观察组;观察组肾动脉阻力指数高于对照组,差异存在统计学意义（P＜0.05）。结论 彩色多普勒超声可以检测高血压病肾动脉血流动力学各项参数,可反映继发性肾灌注的改变,不仅能为肾损伤的早期诊断提供重要依据,还能对患者的预后进行评估,值得临床关注。     

Dopplersonographie der extracraniellen hirnversorgenden und der peripheren Arterien bei Arterioskleroserisikofaktoren und bei KHE

Summary Doppler examination of the neck and limbs of 160 patients with a predisposition to arterial vascular disease in the presence of hypertension, hyperlipoproteinaemia, cigarette smoking and diabetes mellitus, 66% of whom had a combination of two or more of these risk factors, showed in 48 cases single or combined lesions in the arteries of the neck. One patient had unilateral stenosis of the common carotid artery; 20 patients showed unilateral and seven bilateral stenosis of the internal cartid artery; nine patients had unilateral and two patients bilateral stenosis of the external cartid artery; 28 patients showed unilateral flow reduction in the vertebral artery. There was a combined lesion of two or three vessels of the neck in 12 patients. Stenotic peripheral arteries at different levels of the leg with an ankle pressure index decrease of up to 22.5% were detected in 54 patients. These peripheral arterial diseases were associated with stenotic carotid arteries in 28%. Peripheral vascular lesions were present in 40% of patients with stenotic carotid arteries. Of the 160 patients studied 67 had proven coronary heart disease; 22% of these showed stenotic carotid arteries and 29% showed stenotic peripheral arteries. Combined lesions of the coronary, carotid and peripheral arteries were found in 13%.

     

Carotid ultrasonography: evaluation of carotid ultrasonography

Carotid ultrasonography is a laboratory procedure showing how arteriosclerosis screening can diagnose carotid artery occlusion and high-grade stenosis. It is useful for inspection in general practice because of its non-invasiveness, development of sonography equipment, laboratory methods and the establishment of an evaluation method. We generally use a linear array probe of around 7-8MHz for carotid observation and combine the B mode method, color and power Doppler method, and pulsed Doppler method for inspection. At vessel analysis, the intima-media thickness, the property of plaque and stenotic ratio are evaluated. We observe the direction of bloodstream and presence of stricture by Doppler color flow imaging and measure flow velocity and the wave pattern by pulsed Doppler method and, with the B mode method, evaluate the extent or degree of stricture. This can be depicted well using a convex array probe and sector array probe when the mental change caused by disease is deep, and depiction is difficult by linear array probe.     

子痫前期孕妇肾动脉血流参数变化的彩超论断价值

目的探讨彩色多普勒血流显像检测子痫前期孕妇肾动脉血流参数变化的意义。方法本研究随机选取100例正常妊娠妇女为对照组,选取经临床确诊的116例子痫前期患者为研究对象,按病情分为轻度子痫前期60例,重度子痫前期56例。应用彩色多普勒超声检测各组孕妇肾门处肾动脉主干及肾叶间动脉（IRA）收缩期峰值流速（Vs）、舒张末期最低流速（Vd）、上升加速度（AC）、阻力指数（RI）。结果与对照组及轻度子痫前期组比较,重度子痫前期组肾门处及肾内叶间动脉血流参数Vs、RI、AC均明显升高（P〈0．01）,Vd明显下降（P〈0．05）,差异均有统计学意义;而轻度子痫前期组与对照组比较,其肾门处及肾内叶间动脉各项血流参数均无统计学差异（P〉0．05）。结论随着病情严重程度的增加,重度子痫前期患者肾门处及肾内叶间动脉收缩期流速明显升高,阻力增大,而舒张期流速明显减低,彩色多普勒超声无创、可重复性好,能较准确检测子痫前期患者肾动脉血流动力学变化,有较好的临床应用价值。     

Influence of Multiple Stenoses on Echo-Doppler Functional Diagnosis of Peripheral Arterial Disease: A Numerical and Experimental Study

The objective of this paper was to evaluate the ability of the peak systolic velocity ratio (PSVR) and pressure drop (ΔP) to detect and grade multiple stenoses in lower limb mimicking arteries. Numerical simulations and experiments in vascular phantoms allowing ultrasound duplex scanning and pressure measurements were used to investigate simple and double stenotic arterial segments. Inter-stenotic distance, severity of the distal stenosis, flow rate and flow profile (steady or pulsatile) were the tested parameters. The three-dimensional simulations considered the turbulent two-equation Wilcox model. Agreements were observed between the experimental and numerical results for ΔP and PSVR. The maximum PSVR along the artery was shown to be mainly influenced by the severity of the most important stenosis. However, mutual interactions of both stenoses on hemodynamics were noted. By using the clinical PSVR threshold used to diagnose critical lesions (PSVR ≥ 2), its longitudinal evolution along the artery poorly reflected the length of the lesion or the impact of surrounding stenoses. This investigation confirms the interaction between adjacent stenoses on hemodynamics and its impact on the Doppler ultrasound index PSVR.     

Detection of ophthalmic artery stenosis by least-mean squares backpropagation neural network

Doppler ultrasound is a noninvasive technique that allows the examination of the direction, velocity, and volume of blood flow. In this study, ophthalmic artery Doppler signals were obtained from 105 subjects, 48 of whom had suffered from ophthalmic artery stenosis. A least-mean squares backpropagation neural network was used to detect the presence or absence of ophthalmic artery stenosis. Spectral analysis of ophthalmic artery Doppler signals was done by the Welch method for determining the neural network inputs. The network was trained, cross validated and tested with subject records from the database. Performance indicators and statistical measures were used for evaluating the neural network. Ophthalmic artery Doppler signals were classified with the accuracy varying from 88.9% to 90.6%.     

弹性动脉狭窄血管内血液流动的ALE方法分析

针对弹性动脉狭窄血管中血液的流动状况,采用任意拉格朗日-欧拉方法(ALE),在给定相同的边界条件下模拟出了弹性血管和刚性血管中血流速度和压力的变化情况,分析了不同狭窄程度模型的血流状态.结果表明:随着动脉的狭窄程度增加,其中心流速越来越大,窄前压力逐渐升高,窄后压力逐渐降低,狭窄前后的压差单调增加;刚性血管无法对人体正常生理状态进行比较好的模拟,其计算所得结论与实际情况差距较大.说明ALE方法对血液流动的数值研究是可行的.     

Glomerular Filtration Rate Measured by 51Cr-EDTA Clearance: Evaluation of Captopril-Induced Changes in Hypertensive Patients with and without Renal Artery Stenosis

INTRODUCTION:

Renal artery stenosis can lead to renovascular hypertension; however, the detection of stenosis alone does not guarantee the presence of renovascular hypertension. Renovascular hypertension depends on activation of the renin-angiotensin system, which can be detected by functional tests such as captopril renal scintigraphy. A method that allows direct measurement of the baseline and post-captopril glomerular filtration rate using chromium-51 labeled ethylenediamine tetraacetic acid (⁵¹Cr-EDTA) could add valuable information to the investigation of hypertensive patients with renal artery stenosis. The purposes of this study were to create a protocol to measure the baseline and post-captopril glomerular filtration rate using ⁵¹Cr-EDTA, and to verify whether changes in the glomerular filtration rate permit differentiation between hypertensive patients with and without renal artery stenosis.

METHODS:

This prospective study included 41 consecutive patients with poorly controlled severe hypertension. All patients had undergone a radiological investigation of renal artery stenosis within the month prior to their inclusion. The patients were divided into two groups: patients with (n=21) and without renal artery stenosis, (n=20). In vitro glomerular filtration rate analysis (⁵¹Cr-EDTA) and ^99mTc-DMSA scintigraphy were performed before and after captopril administration in all patients.

RESULTS:

The mean baseline glomerular filtration rate was 48.6±21.8 ml/kg/1.73 m² in the group wuth renal artery stenosis, which was significantly lower than the GFR of 65.1±28.7 ml/kg/1.73m² in the group without renal artery stenosis (p=0.04). Captopril induced a significant reduction of the glomerular filtration rate in the group with renal artery stenosis (to 32.6±14.8 ml/ kg/1.73m², p=0.001) and an insignificant change in the group without RAS (to 62.2±23.6 ml/kg/1.73m², p=0.68). Scintigraphy with technetium-99m dimercapto-succinic acid (DMSA) did not show significant differences in differential renal function from baseline to post-captopril images in either group.

CONCLUSIONS:

Captopril induced a decrease in the GFR that could be quantitatively measured with ⁵¹Cr-EDTA. The reduction is more pronounced in hypertensive patients with RAS.     

彩色多普勒检测子宫动脉预测妊高征的价值研究

目的探讨彩色多普勒检测子宫动脉预测妊娠高血压综合征（妊高征）的价值及临床意义。方法应用彩色多普勒超声对587例20～24周妊娠妇女的子宫动脉进行检测,通过观察追踪随访孕妇至分娩,根据是否出现高血压,把检测20～24周妊娠妇女的子宫动脉参数分为两组：正常组（560例）和高危组（27例）,进行对照研究,对比分析两组受检者子宫动脉血流动力学变化及声像图表现。结果①高危组子宫动脉收缩期峰值血流速度（Vd）较正常组快,舒张期最小血流速度（Vs）和平均血流速度（Vm）减慢（P〈0.01）,高危组子宫动脉阻力指数（RI）、搏动指数（PI）和收缩期峰值血流速度/舒张期最小血流速度（S/D）比正常组高（P〈0.01）,②高危组子宫动脉多普勒频谱表现典型者出现舒张早期＂V＂切迹。结论高危组患者子宫动脉血流动力学和多普勒频谱形态与正常组妊娠妇女有明显的不同,常规定期监测20～24周妊娠妇女子宫动脉血流动力学变化及多普勒频谱形态,对早期发现和治疗妊高征,保障母婴健康具有极其重要的意义。     

肝移植术后肝动脉狭窄频谱Tardus Parvus波形和超声造影微灌注定量技术的临床价值

目的　探讨肝移植术后肝动脉狭窄频谱Tardus Parvus波形和超声造影微灌注定量技术的临床意义。 方法　收集60例肝移植术后病人的相关影像资料,记录肝动脉多普勒超声的收缩期峰值血流速度（PSV）、舒张末期血流速度（EDV）、阻力指数（RI）及加速时间（SAT）等参数,Tardus Parvus波形的诊断标准为RI＜0.5且SAT＞0.8 s;超声造影分别记录肝边缘区域和中心区实质基础强度（BI）、到达时间（AT）、峰值强度（PI）、达峰时间（TTP）及中心区域与边缘区域的实质增强程度差异绝对值（REI）等定量参数,以CTA或DSA诊断肝动脉直径狭窄率≥50%为标准,将患者分为肝动脉狭窄组和非狭窄组。 结果 肝动脉狭窄组多普勒超声表现为Tardus Parvus波形阳性（P<0.05),超声造影狭窄组与非狭窄组相比,REI减小（P<0.05）,中心区域TTP延长（P<0.05）。 结论　Tardus Parvus波形和超声造影微灌注定量技术对肝移植术后肝动脉狭窄诊断具有一定的价值。     

Coupled fluid-wall modelling of steady flow in stenotic carotid arteries

Arterial stenoses may cause critical blood flow and wall conditions leading to clinical complications. In this paper computational models of stenotic carotid arteries are proposed and the vessel wall collapse phenomenon is studied. The models are based on fluid-structure interactions (FSI) between blood and the arterial walls. Coupled finite element and computational fluid dynamics methods are used to simultaneously solve for stress and displacement in the solid, and for pressure, velocity and shear stress in the fluid domain. Results show high wall shear stress at the stenosis throat and low (negative) values accompanied by disturbed flow patterns downstream of the stenosis. The wall circumferential stress varies abruptly from tensile to compressive along the stenosis with high stress concentration on the plaque shoulders showing regions of possible plaque rupture. Wall compression and collapse are observed for severe cases. Post-stenotic collapse of the arterial wall occurs for stenotic severity as low as 50%, with the assumption that a given amount of blood flow needs to pass the stenotic artery; whereas if constant pressure drop should be maintained across a constriction, then collapse happens at severity of 75% and above. The former assumption is based on the requirement of adequate blood supply to the downstream organs/tissue, while the latter stems from the fact that the pumping mechanism of the body has a limited capacity in regulating blood pressure, in case a stenosis appears in the vasculature.     

Early graft hemodynamics in living related liver transplantation evaluated by Doppler ultrasonography

The aim of this study was to clarify the perioperative hemodynamics of liver grafts without vascular complications during and early after liver transplantation from living donors. This study was carried out in 4 child recipients (lateral segment left lobe grafts) and 6 adult recipients (right lobe grafts) of liver transplantation from living donors. The hemodynamics of the hepatic artery, portal vein, and hepatic vein of the grafts during and until 7 days after surgery were studied by Doppler ultrasonography. The maximum flow velocity of the hepatic artery, mean portal blood flow velocity, and pulsatility index (PI) of the hepatic artery increased in all 10 grafts with no vascular complication after vascular anastomosis. After surgery, the mean portal blood flow velocity showed a peak 3 days after surgery and reached a nadir 7 days after surgery in both the lateral segment left lobe grafts in children and the right lobe grafts in adults, but it was significantly higher in the right lobe grafts in adults (mean +/- SD 31.0 +/- 6.3 vs. 22.4 +/- 0.9 cm/sec). Also, as the hepatic artery blood flow velocity increased the portal blood flow velocity decreased, the hepatic blood flow during liver regeneration was suggested to be controlled by both the artery and portal vein. The range of PI of the hepatic artery was 0.60-1.86. The mean hepatic venous blood flow was stable throughout the observation period (30.4 +/- 8.8 cm/sec). Although the hepatic venous flow waves changed widely from pulsed waves to a flat flow, its changes did not suggest a vascular complication. Evaluation of changes by Doppler ultrasonography in the hemodynamics of the liver grafts without vascular complications during and early after liver transplantation from living donors is considered to be useful for accurate monitoring of the hemodynamics during liver regeneration and early detection of abnormalities.     

Arterial hypertension in renal transplant recipients

Arterial hypertension develops in up to 80% of renal transplant recipients. Uncontrolled hypertension induces left ventricular hypertrophy, heart failure and death, but also promotes deterioration of allograft function. Cadaveric transplantation, delayed graft function, renal artery stenosis, presence of native kidneys, increased body weight and therapy with calcineurin inhibitors and steroids have been associated with an increased incidence of hypertension after kidney transplantation. Cyclosporine increases both systemic and renal vascular resistance, enhances sympathetic activation, endothelin production and, possibly, decreases vascular relaxation by decreasing the generation of nitric oxide. Tacrolimus has less pronounced prohypertensive role after renal transplantation. Corticosteroids contribute to the development of hypertension, since their withdrawal results in a significant decrease of blood pressure in the majority of patients. Renal artery stenosis occurs in almost 12% of hypertensive renal transplant recipients. It is a correctable cause of hypertension, and for this reason should be investigated in all suspected patients. Doppler ultrasonography is used as the screening method that is highly sensitive and specific in the hands of a well-experienced investigator. However, dependence of the method on the experience of the investigator is its major drawback. Magnetic resonance angiography and spinal computed tomography angiography are useful noninvasive methods, but arteriography remains a method for establishing the definitive diagnosis. Percutaneous balloon angioplasty, with or without placement of the stent, is successful in the majority of patients, but with a high incidence of restenoses (20%). Surgery is indicated for stenoses that cannot be treated with angioplasty or that recur. Auto-transplantation of the kidney with complex stenoses of graft arteries is useful in selected cases. Posttransplant hypertension should be aggressively treated to prevent the development of end-organ damage. Every effort should be invested in reducing immunosuppression when appropriate, together with salt restriction and weight reduction. Calcium channel blockers have good antihypertensive properties accompanied with minimization of cyclosporine-induced renal vasoconstriction. Angiotensin-converting enzyme inhibitors (ACEi) should be used in patients with proteinuria. Renal function should be carefully monitored after their introduction since they may cause transitory deterioration of glomerular filtration and/or hyperkaliemia. ACEi can induce anemia in renal transplant recipients, side effect that is often used in the treatment of posttransplant erythrocytosis. All other antihypertensive drugs could be used, with minoxidil being the most potent one. Patients with resistant hypertension should be investigated for the presence of renal artery stenosis. After exclusion of rejection, renal artery stenosis and recurrent disease, in cases of severe hypertension, native kidneys laparoscopic nephrectomy should be considered.     

气管、支气管狭窄患者计算机气流动力学模拟参数改变及其临床意义

目的 探讨气管、支气管狭窄患者气流动力学参数的改变及意义。方法 选取2011年1月—2015年12月徐州医学院附属医院40例气管、支气管狭窄患者(观察组)及40名健康体检者(对照组)的临床、影像及肺功能资料进行回顾性分析。依据病变部位不同观察组又分为气管狭窄组、支气管狭窄组各20例;其中恶性狭窄38例,气道狭窄程度>50%者30例,腔外型狭窄为20例,弥漫型狭窄22例,偏心性狭窄37例。应用螺旋CT机采集感兴趣区DICOM数据,利用医学影像3D重建软件建立气道几何模型;将肺功能数据施加到几何模型出入口边界后,应用计算机流体力学分析软件进行气道气流动力学模拟,记录感兴趣区气流动力学截面积、流速、体积流量等参数进行统计学分析,不同参数组内比较采用配对t检验。结果 所有研究对象气流动力学研究模型成功建立。气管、支气管狭窄组狭窄处流速分别为(1 764±1 484)cm/s、(156±57)cm/s,流量分别为(1 565±963)mL/s、(310±99)mL/s,均高于同组气管、支气管入口流速及流量(P<0.05或P<0.01) ;支气管狭窄组患侧支气管入口流速及流量为(82±35)cm/s及(79±32)mL/s,分别小于健侧支气管入口流速(211±83)cm/s及流量(184±68)mL/s(P值均<0.01);在15例偏心性气管狭窄患者中,和原发病变同侧支气管入口流速及流量分别为(464±246)cm/s及( 526±283)mL/s,高于病变对侧支气管入口流速(308±209)cm/s及流量(359±255)mL/s(P值均<0.05)。对照组气管及双侧支气管入口分别与气管、支气管中段流速及流量比较,差异均无统计学意义(P值均>0.05)。结论 气管、支气管狭窄患者气流动力学参数存在着一定的病理性改变。气管狭窄引起狭窄处气体流速、流量增加,且偏心性狭窄影响两侧支气管气流;支气管狭窄则引起患侧进入气流减少。计算机气流动力学参数模拟可以融合多种检查数据,对研究该病呼吸病理生理及病情评估提供了一种新的综合性评价方法。     

Bilateral photoplethysmography for arterial steal detection in arteriovenous fistula using a fractional-order decision-making quantizer

As inflow and outflow stenoses worsen, both flow resistance and pressure increase in the stenotic vascular access. During dialysis, when blood flow decreases, it may retrograde from the peripheral artery through the palmar arch to the arterial anastomosis site. Arterial steal syndrome (ASS) causes distal hypoperfusion, resulting in hand ischemia or extremity pain and edema. Hence, this study proposes the bilateral photoplethysmography (PPG) for ASS detection in arteriovenous fistulas. The decision-making quantizer utilizes the fractional-order feature extraction method and a non-cooperative game (NCG) framework to evaluate the ASS risk level. Bilateral asynchronous PPG signals have significant differences in the rise time and amplitude in relation to the degree of stenosis. The fractional-order self-synchronization error formulation is a feature extraction method used to quantify bilateral differences in blood flow changes between the dexter and sinister PPG signals. The NCG model as a method of decision-making is then employed to evaluate the ASS risk level. Using an acoustic Doppler measurement, the resistive (Res) index is also used to evaluate the vascular access stenosis at the arterial anastomosis site. In contrast with alternative methods including the high-sensitivity C-reactive protein level or Res index, our experimental results indicate that the proposed decision-making quantizer is more efficient in preventing ASS during hemodialysis treatment.     

颈动脉彩色多普勒超声对老年高血压患者颈动脉病变情况诊断价值

目的探讨颈动脉彩色多普勒超声对老年高血压患者颈动脉病变情况诊断价值。方法抽取60例老年高血压患者与57例健康者分别设为病例组与对照组,均行颈动脉彩色多普勒超声,比较两组检查结果。结果病例组颈动脉狭窄率为88.3%,斑块形成率为80.00%,内膜中层厚度(IMT)、颈动脉内径(D)、阻力指数(RI)均较对照组高(P <0.05);病例组颈内动脉、颈总动脉最大剪切率(SR)以及收缩期峰值流速(PSV)均低于对照组(P <0.05)。结论颈动脉彩色多普勒超声对老年高血压患者颈动脉病变具有较高诊断价值,值得推广。     

妊高征孕妇胎盘微循环功能与脐动脉血流的相关性研究

胎盘微循环功能的监测是产科医生进行临床决策的重要参考内容,它与胎儿胎盘循环直接相关,关系到产科质量的优劣和围产儿的预后。过去常通过查尿雌三醇、尿雌激素／肌酐比值（ｅｓｔｒｉｏｌ／ｃｒｅａｔｉｎｉｎｅ,Ｅ／Ｃ值）等间接监测胎盘微循环功能。目前应用超声多普勒测定脐动脉血流阻力已成为产科监护较理想的手段之一［１,２］,故我们选用超声多普勒测定妊高征孕妇脐动脉血流速度波型收缩期峰值／舒张末期峰值（ｓｙｓｔｏｌｉｃｐｅｒｉｏｄｃｒｅｓｔｖａｌｕｅ／ｄｉｓｔｏｌｉｃｅｎｄｐｅｒｉｏｄｃｒｅｓｔｖａｌｕｅ,…     

Doppler ultrasound measurement of phasic renal arterial blood flow velocity in patients with chronic glomerulonephritis]

The phasic renal arterial blood flow velocity was measured using a Doppler-Based Toshiba SSH-160A scanner in 25 healthy subjects and 78 patients with chronic glomerulonephritis. Renal arterial blood flow at the renal hilum was visualized with color Doppler ultrasound, and the velocity waveform was obtained by pulsed Doppler ultrasound. The velocity waveform was then analyzed to give the peak systolic velocity (S), end-diastolic velocity (D), resistive index (RI), and pulsatility index (PI). Creatinine clearance correlated with S (r = 0.76), D (r = 0.80), RI (r = -0.74), and PI (r = -0.85). The split renal glomerular filtration rate, calculated by a method which makes use of the early renal uptake of Tc-99m DTPA, also correlated well with these parameters. These findings suggest that renal arterial blood flow as detected by Doppler ultrasound may be useful for the noninvasive, direct, rapid, and simple evaluation of renal hemodynamics and renal function, although various modifying factors also need to be considered.     

The prevalence and associated risk factors of renal artery stenosis in patients undergoing cardiac catheterization

Renal artery stenosis may be a cause of hypertension and a potential contributor to progressive renal insufficiency. However, the prevalence of renal artery disease in a general population is poorly defined. The purposes of this study were to evaluate the prevalence of angiographically-determined renal artery narrowing in a patient population undergoing routine cardiac catheterization, and to identify the risk factors for renal artery stenosis. After left ventriculography, abdominal aortography was performed to screen for the presence of renal artery stenosis. A total of 427 patients (274 males, 153 females) were studied and the mean age was 59 years. Renal artery narrowing was identified in 10.5% of patients. Significant (> or = 50% diameter narrowing) renal artery stenosis was found in 24 patients (5.6%) and insignificant stenosis was found in 21 patients (4.9%). Significant unilateral stenosis was present in 4.2% of patients and bilateral stenosis was present in 1.4%. The stem of the renal artery was a more common site of stenosis in 62.2% of patients than in the ostium (37.8%), but the severity of stenosis was not significantly different according to the site of stenosis. By univariate and multivariate logistic regression analysis, the association of clinical variables with renal artery stenosis was assessed. Multivariable predictors included age, hypertension and peripheral vascular disease (p < 0.05). The variables such as sex, smoking history, hyperlipidemia, renal insufficiency, as well as the presence of obesity, severity of coronary heart disease and D.M., were not associated. In conclusion, the prevalence of angiographically-determined renal artery narrowing in a patient population undergoing cardiac catheterization is 10.5%. Old age, hypertension and evidence of peripheral vascular disease represent the predictors of renal artery stenosis.     

多层螺旋CT图像后处理诊断移植肾动脉狭窄

背景：对肾移植后并发移植肾动脉狭窄患者的诊断及随访是否可采用一种无创伤、特异性高、安全的检查方法。 目的：评估多层螺旋CT图像后处理技术对移植肾动脉狭窄的诊断价值。 方法：对11例临床怀疑为移植肾动脉狭窄的患者进行移植肾动脉期的增强扫描,扫描后所得到的数据经容积重建、最大密度投影、曲面重建、多平面重建处理成像。 结果与结论：11例患者均诊断为移植肾动脉狭窄,10例多层螺旋CT图像后处理技术显示移植肾动脉狭窄程度54%~75%,1例移植肾动脉狭窄程度< 50%。吻合口狭窄10例,其中合并移植肾动脉主干狭窄2例;移植肾动脉分支狭窄1例。经数字减影血管造影检查9例,狭窄程度75%~95%,8例置入支架,1例球囊扩张;1例给予药物治疗随访,于2年后出现肾功能进一步恶化及难治性高血压,置入支架。1例无临床症状,经多层螺旋CT移植肾动脉狭窄程度< 50%,随访4年肾功能、血压正常。支架置入治疗的患者中1例行球囊扩张者2年后彩色多普勒提示移植肾吻合口狭窄,行多层螺旋CT检查移植肾动脉狭窄程度< 50%,随访4年3个月,肾功能、血压正常。提示多层螺旋CT后成像技术可作为移植肾动脉狭窄的诊断依据,对区分临床疑似病例,制定支架置入治疗方案,以及术后随访观察有一定的临床参考价值。