Retroaortic left renal vein joining the left common iliac vein

Retroaortic left renal vein joining the left common iliac vein is a rare congenital anomaly in the development of the inferior vena cava. To our knowledge, only one case has been reported in the literature; however, its imaging features have never been described. A 27-year-old male presented with a 1-year history of recurrent right flank pain, dysuria, hematuria, and fever (39 °C). Computed tomography and MR venography showed a retroaortic left renal vein joining the left common iliac vein. We present the CT and MR venography findings and discuss their feasibility in showing this congenital anomaly. Received: 18 October 1999; Revised: 11 February 2000; Accepted: 15 February 2000     

Aorta-Left Renal Vein Fistula Complicating an Aortic Aneurysm: Preoperative and Postoperative Multislice CT Findings

Fistulas complicating an abdominal aortic aneurysm (AAA) are rare, and fistulas involving the left renal vein are particularly uncommon. We highlight here a fistula between an infrarenal aortic aneurysm and a retroaortic left renal vein, revealed by left flank pain associated with hematuria and acute renal failure. The multislice CT angiography performed in this 68-year-old patient revealed communication and equal enhancement between the aorta and the left gonadic vein, suggesting the presence of a fistula. The three-dimensional VRT reconstructions presented in this case were of great value in the preoperative planning, enabling immediate visualization of this unusual feature. Alternative diagnoses to consider when encountering this clinical presentation are reviewed.     

MR-angiographic diagnosis of an aberrant retroaortic left renal vein and review of the literature

MR-angiography is suitable for depiction of developmental vascular anomalies such as an aberrant left renal vein. We report MRA findings of one case of a retroaortic left renal vein and the review of the literature.     

Posterior Nutcracker Syndrome Associated with Interrupted Left Inferior Vena Cava with Azygos Continuation and Retroaortic Right Renal Vein

Various anatomic anomalies have been considered the causes of nutcracker syndrome (NCS). Posterior NCS refers to the condition, in which vascular narrowing was secondary to the compression of the retroaortic left renal vein while it is crossing between the aorta and the vertebral column. Here, we report an unusual case of posterior NCS associated with a complicated malformation of the interrupted left inferior vena cava with azygos continuation and retroaortic right renal vein, diagnosed by both color Doppler ultrasonography and CT angiography.     

Retroaortic left renal vein: an interpretive pitfall on computed tomography

In a patient with retroaortic left renal vein, the anomalous vessel is demonstrated by computed tomography to take a caudal course of several centimeters before crossing in a retroaortic fashion to join with the inferior vena cava. This case differs from previously published reports. Computed tomography provided excellent anatomic details of the vascular anomaly and highlighted the value of postcontrast dynamic computed tomography scanning.     

Nutcracker or left renal vein compression phenomenon: multidetector computed tomography findings and clinical significance

The use of multidetector computed tomography (MDCT) in routine abdominal explorations has increased the detection of the nutcracker phenomenon, defined as left renal vein (LRV) compression by adjacent anatomic structures. The embryology and anatomy of the nutcracker phenomenon are relevant as a background for the nutcracker syndrome, a rare cause of hematuria as well as other symptoms. MDCT examples of collateral renal vein circulation (gonadal, ureteric, azygous, lumbar, capsular) and aortomesenteric (anterior) and retroaortic (posterior) nutcracker phenomena in patients with no urologic complaint are shown as well as studies performed on patients with gross hematuria of uncertain origin. Incidental observation of collateral veins draining the LRV in abdominal MDCT explorations of asymptomatic patients may be a sign of a compensating nutcracker phenomenon. Imbalance between LRV compression and development of collateral circulation may lead to symptomatic nutcracker syndrome.     

Retroaortic left renal vein: multidetector computed tomography angiography findings and its clinical importance

PURPOSE: To evaluate the appearance, type, frequency, and clinical importance of retroaortic left renal vein (RLRV) in patients examined with multidetector computed tomography (MDCT) angiography. Material AND METHODS: A total of 1856 patients who underwent CT with urological symptoms (hematuria, flank and abdominal pain, left gonadal vein varicocele) (n = 889) or with symptoms other than urological ones (n = 967) were prospectively evaluated for the presence of RLRV. CT was performed with 110 ml of iodinated contrast material through the antecubital vein at a rate of 3.5 ml/s. Late arterial and early venous phase volumetric data sets were acquired at 30 and 65 s, respectively, from the start of the intravenous injection of contrast medium. In addition to axial images, multiplanar reconstructions (MPR), maximum-intensity projection (MIP), and three-dimensional volume-rendering (3D VR) images were used to assess left renal vein anomalies. Left renal vein anomalies were classified into four types according to their appearance: I) RLRV joining the inferior vena cava (IVC) in the orthotopic position; II) RLRV joining the IVC at level L4-L5; III) circumaortic or collar left renal vein; IV) RLRV joining the left common iliac vein. RESULTS: RLRV was detected in 68 (3.6%) of the 1856 patients, with 26, 22, 17, and three of types I, II, III, and IV, respectively. Forty-four of the 68 patients with RLRV (65%) were in the group with urological symptoms, while 24 patients (35%) were in the group without urological symptoms. Compression of the RLRV was found in 16 patients in the urological symptoms group, while compression was detected in only three patients in the other group. This difference was statistically significant (P<0.05). The most common urological symptom was hematuria. The frequency of urological symptoms was higher in groups II and IV compared to the other groups. CONCLUSION: MDCT angiography with axial, MPR, MIP, and 3D VR images is effective in the detection of vascular renal anomalies such as RLRV. Diagnosing RLRV and differentiating it from other pathologic conditions causing hematuria is important in order to avoid complications during retroperitoneal surgery or interventional procedures.     

Double retroaortic left renal veins as a possible cause of pelvic congestion syndrome: imaging findings in two patients

Pelvic congestion syndrome is characterized by chronic pelvic pain and varicose veins around the uterus and ovaries. We report two cases of double retroaortic left renal vein, associated with left-sided pelvic congestion syndrome, diagnosed by CT and confirmed by clinical findings and colour Doppler ultrasound. Double retroaortic left renal veins may be a contributing factor for the development of left pelvic congestion syndrome. This is the first report of double retroaortic left renal vein and associated pelvic congestion syndrome.     

The Nutcracker Syndrome

Nutcracker syndrome (NCS) is a rare condition caused by the compression of the left renal vein between the abdominal aorta and the superior mesenteric artery. NCS may present with unexplained hematuria. This case report presents a 43-year-old healthy female without any complaints who had newly-detected hematuria in urinalysis during her annual examination. Her physical examination and the whole abdominal ultrasonography failed to explain the cause of hematuria. Further investigation with contrast-enhanced upper abdominal computed tomography revealed a NCS. In unexplained cases of asymptomatic hematuria NCS should be taken into account after excluding other preliminary diagnoses.     

Retroaortic renal vein with tumor thrombus: MR findings

The magnetic resonance (MR) findings in a case of tumor extension into a retroaortic renal vein from a renal cell carcinoma are reported. The signal characteristics of the tumor thrombus paralleled those of the renal mass, and the preoperative recognition of the anomalous vessel lead to an altered surgical approach.     

Retroaortic renal vein with tumor thrombus: MR findings.

The magnetic resonance (MR) findings in a case of tumor extension into a retroaortic renal vein from a renal cell carcinoma are reported. The signal characteristics of the tumor thrombus paralleled those of the renal mass, and the preoperative recognition of the anomalous vessel lead to an altered surgical approach.     

动脉晚期CTA融合图像在肾动静脉系统评估中的价值

目的探讨动脉晚期CTA融合图像在肾动静脉系统评估中的价值。方法26例超声提示肾占位的病人及5例活体供肾者,采用德国Siemens Somatom Sensation 16层螺旋CT机,进行了平扫及动脉早期、动脉晚期及实质期3期增强扫描。数据被传到GE ADW 4.2 Workstation进行3D重建,采用Volume viwer plus voxtool 6.3.19软件包。由2位放射科主任医师对肾动静脉系统显示情况进行评估,意见相左时,通过讨论达成共识。结果动脉晚期CTA融合图像对副肾动脉和肾动脉提前分支的显示率与动脉早期相同。左右肾副肾动脉的CTA显示率分别为32.3%和6.5%。左右肾动脉提前分支的显示率分别为12.9%和9.7%。对环主动脉左肾静脉、腹主动脉后左肾静脉及多条右肾静脉,动脉晚期CTA融合图像与实质期的显示率之间亦无差异,分别为16.1%、3.2%及32.3%。动脉晚期CTA融合图像对左肾上腺静脉、左性腺静脉及左腰静脉的显示率为83.9%、87.1%、61.3%,和实质期相比(分别为87.1%、93.5%、64.5%),2组之间无统计学差异(P>0.05)。动脉晚期CTA融合图像质量优于实质期。结论动脉晚期CTA融合图像能够同时且清楚地显示肾动静脉系统,减少了受检者的放射线剂量、节约了检查时间。     

64层螺旋CT对肾静脉解剖变异的研究

目的 利用64层螺旋CT血管造影探讨肾静脉解剖变异的类型及其临床意义.资料与方法 回顾性分析280例患者的64层螺旋CT肾静脉影像资料,观察肾静脉的解剖变异并进行分型.结果 肾静脉解剖变异的发生率为7.1%(20/280).右肾静脉变异8例,均为副肾静脉.左肾静脉变异13例,包括Ⅰ型(环主动脉左肾静脉)4例,Ⅱ型(主动脉后左肾静脉)1例,Ⅲ型(回流异常)3例,Ⅳ型(左肾静脉汇合过晚)5例(其中1例伴右副肾静脉).11例肾静脉变异患者同时伴有肾动脉变异.结论 64层螺旋CT血管造影可清晰显示肾静脉解剖变异,结合肾动脉解剖变异,可为Ⅰ临床提供可靠的肾血管系统解剖学资料.     

Clinical significance and renal haemodynamics of incidentally detected retroaortic left renal vein: assessment with venous Doppler sonography

The purpose of this study was to determine whether renal venous pulsations are affected by compression of the left renal vein (LRV) between the aorta and spine, and also to determine the clinical significance of incidentally detected retroaortic LRV. The study population was recruited from 783 consecutive patients undergoing abdominal CT examination for various indications. 22 patients with a retroaortic LRV were prospectively enrolled in this study, and 22 patients without renal disease served as a control group. After measuring the diameters of the central and peripheral portions of the LRV on CT images, the ratio (P/C) and difference (P-C) of the diameters were calculated. Doppler sonography of the interlobar arteries and veins of the left kidney was then performed to obtain impedance indices. Urine analysis of all subjects and scrotal colour Doppler ultrasound of male patients were also performed. The retroaortic LRV diameters were significantly narrower than the pre-aortic LRV diameters (p = 0.002). The left intrarenal venous impedance indices were significantly higher in the patients with retroaortic LRV (p = 0.026) and in the subgroups with P/C>2 (p = 0.020), with P-C>4 mm (p = 0.007) and without nutcracker-like associations (p = 0.006) than in control subjects, but no significant difference was noted between the arterial resistance indices. Haematuria (n = 8), proteinuria (n = 4), varicocele (n = 3) and collaterals (n = 1) were detected in the study group but not in the control group. In conclusion, incidentally detected retroaortic LRV appears to be associated with haematuria, proteinuria, varicocele and altered venous pulsatility. Further investigations are needed to understand the role of venous Doppler ultrasound in the nutcracker phenomenon.     

膜性肾病并发肾静脉血栓的彩色多普勒超声表现分析

目的探讨膜性肾病患者并发肾静脉血栓的彩色多普勒超声表现及其临床意义。方法膜性肾病27例,用二维超声和彩色多普勒超声观察肾脏的大小、形态、内部回声及肾静脉内是否有血栓。结果 27例中左肾主静脉血栓形成6例,段支1例,右肾主静脉血栓形成3例,段支1例,双肾主静脉血栓形成1例,本组27例膜性肾病患者并发肾静脉血栓的发生率为44%。结论彩色多普勒超声可作为诊断肾静脉血栓的首选方法。     

左肾静脉及其属支的MSCTA

目的：探讨左肾静脉及其属支的64层MSCTA技术及其影像表现。方法：分析连续100例患者MSCT增强扫描动脉期和静脉期图像上左肾静脉及其各属支的显示情况。MSCT检查采用64层CT机,0.625mm×64i方式采集,0.625mm层厚回顾性重建,标准或软组织算法;对比剂剂量80～90ml,注射流率3～4ml/s,延迟时间动脉期为25～26s、静脉期50～60s。后处理采用三维正交多平面重组（OMPR）、最大密度投影（MIP）和容积再现（VR）三种方法。结果：MSCTA动脉期和静脉期图像上均完整显示左肾静脉主干,静脉期图像上对其3个属支的显示数量（276支）多于动脉期（217支）。VR图像显示这些血管最好。69%的病例为标准的单支左肾静脉和3个属支（肾上腺静脉、生殖腺静脉和腰静脉）,31%的病例有不同程度的变异,部分病例可清楚显示膈静脉（23例）和肾包膜静脉（27例）的汇入。结论：MSCTA静脉期图像结合三维重组技术可以清晰显示左肾静脉及其属支,其中以VR图像最佳;大部分受试者的左肾静脉及属支为标准的单支型,但变异类型较多。     

成人胡桃夹综合征介入诊治(附4例报告)

目的探讨成人胡桃夹综合征的临床特点及介入诊治的价值方法4例患者19～39岁,均在外院误诊误治,主要表现为下腹持续疼痛、经量增多、经期延长或反复肉眼血尿B超、CTA及MRA示肾静脉远端扩张或盆腔静脉曲张3例行左肾静脉内放置自膨式支架,1例行左肾静脉重建术结合文献讨论其发病、临床及影像学特点和介入诊治的价值结果术后症状消失,3月及6月分别复查B超和CT示左肾静脉通畅,尿常规正常结论左肾静脉压迫综合征具有一定的临床特点,介入内支架治疗可解除左肾静脉受压     

Incidence of retro-aortic left renal vein and its relationship with varicocele

The retro-aortic left renal vein (RLRV) is a malformation characterized by the presence of a vessel that drains the left renal blood up to the inferior vena cava crossing behind the aortic artery. Varicocele is defined as venous dilation of the pampiniform plexus, and the left side is the most commonly affected. Several theories concerning the possible aetiology of varicocele are reviewed in the literature, but RLRV was not mentioned as an aetiologic factor of varicocele. in this study we investigated the percentage of RLRVs and their relation with varicocele. A total of 1,125 contrast-enhanced abdominal CT scans was examined to identify RLRVs. RLRVs were found in nine women (1.6%) and ten men (1.7%). We performed scrotal Doppler ultrasonography (US) for all affected men except one. Varicocele of varying degrees was found in seven of the nine male patients with RLRV (77%). RLRV could be one of the aetiological factors in the development of varicocele, and the cases with RLRV should be examined by scrotal Doppler US for the presence of varicocele.     

Congenital anomalies and anatomical variants of the inferior vena cava and left renal vein: noninvasive diagnosis with duplex Doppler sonography

The sonographic findings in five patients with congenital anomalies of the interior vena cava and left renal vein are presented. We encountered two patients with duplication and two with transposition of the inferior vena cava, and one with a retroaortic left renal vein, In four cases the findings were confirmed by demonstrating venous flow within the anomalous vascular structures using duplex Doppler equipment. The diagnostic capabilities of sonographic imaging and Doppler analysis of blood flow allow noninvasive recognition of these vascular anomalies. In our opinion, invasive studies are needed only when retroperitoneal structures are difficult to assess by ultrasound because of obesity and/or abundant overlying intestinal gas.     

Translumbar repair of a type II endoleak associated with an aorta-to-left renal vein fistula after aortic stent-graft placement

An abdominal aortic aneurysm (AAA) is a serious medical condition with significant associated morbidity and mortality. Endograft repair of AAAs is a therapy in evolution, but offers promise as a minimally invasive treatment option. Persistent sac pressurization via endoleaks has limited wider application of stent-grafting technology. The present report describes a case of an AAA with rupture into a retroaortic left renal vein that was treated acutely with aortic stent-graft repair. Continued aneurysm enlargement and a large type II endoleak drained by an arteriovenous fistula were subsequently treated via a translumbar approach.