Resection of extensive segments of inferior vena cava without reconstruction in the treatment of renal carcinoma with inferior vena cava tumor thrombus: A case report.

We present a 55-year-old male patient with right renal carcinoma with long inferior vena cava (IVC) tumor thrombus who underwent robot-assisted laparoscopic radical nephrectomy with extensive IVC resection and left renal vein ligation. The patient had a history of hematuria only prior to admission. Our case involved resection of the entire abdominal segment of the IVC and left renal vein without reconstruction. Unfortunately, the patient passed away over a year after the surgery due to brain metastasis.

Morphometry and skeletopy of kidneys and renal vessels in marmoset (Callithrix spp.).

BACKGROUND: Marmosets, Callithrix spp, are small New World monkeys that have gained importance as an experimental animal model for human. Despite its use, information on its renal morphometry, vascularization, and location are limited. Therefore, this study will supply basic anatomy for applied studies and for comparative anatomy. METHODS: Fifty cadavers of Callithrix spp were collected on highways from the Atlantic Forest biome, identified and injected with a 10% formaldehyde solution. Later, the specimens were dissected and the measurements and topography of the kidneys and renal vessels were recorded. Both left and right kidneys were significantly larger in females. RESULTS: In the specimens studied, the average body length was 20.00 ± 2.46 cm in males and 20.50 ± 1.98 cm in females (p = .43). The kidneys of the Callithrix spp. were symmetrical in shape and resembled a "bean." They were also pale brown with a smooth surface. In males, the most frequent location of the right kidney was at the L1-L2 level (92%), while the location of the left kidney was between L2 and L3 (76%). In females, the most frequent location of the right kidney was at the L1-L2 level (56%), while the location of the left kidney was between L2 and L3 (32%) (Table 1). However, in seven (28%) males and nine (36%) females, the kidneys were at the same level. CONCLUSIONS: In both sexes, there was a positive and significant linear correlation between body length and kidney length. Regardless of the variable location of the kidneys in both sides and in either sexe, the right kidney was always located more cranially than the left, similar to observations in other non-human primates.

Migration of sclerosant material to the left renal vein following coil embolisation of a varicocele.

Percutaneous testicular varicocele embolisation for symptomatic and subfertile males is often preferred over surgical ligation of the gonadal vein due to its minimally invasive approach and reduced complication rate. Glues, coils, vascular plugs, balloons and sclerosants are used in various combinations to achieve sufficient venous occlusion. Here, we report on the first known case of sclerosant material migration beyond the placement of an embolisation coil for treatment of a varicocele, resulting in a left renal vein thrombus. A man in his 20s presented to the emergency department 2 days following uncomplicated left varicocele embolisation with acute left-sided abdominal pain, found to have sclerosant material causing an ipsilateral non-occlusive left renal vein thrombus with extension towards his inferior vena cava on CT. He was treated with 3 months of anticoagulation and follow-up imaging at 3 months showed resolution of this thrombus without renal impairment.

Improvements and challenges in intraperitoneal laparoscopic para-aortic lymphadenectomy: The novel "tent-pitching" antegrade approach and vascular anatomical variations in the para-aortic region.

INTRODUCTION: This study introduces and compares a new intraperitoneal laparoscopic para-aortic lymphadenectomy method to reach the level of the renal vein, the "tent-pitching" antegrade approach with the retrograde approach in gynecological malignancy surgeries in terms of success rate, complication incidence, and the number of lymph nodes removed. It focuses on the feasibility, safety, and effectiveness. Meanwhile, this article reports on the vascular anatomical variations discovered in the para-aortic region to enhance surgical safety. MATERIAL AND METHODS: This was a retrospective cohort study including patients undergone laparoscopic para-aortic lymphadenectomy at a single center from January 2020 to December 2023 for high-risk endometrial and early-stage ovarian cancer. Patient charts were reviewed for mode of operation, perioperative complications, operative details, and histopathology. The patients were divided into anterograde group and retrograde group according to the operation mode. The two groups were further compared based on the success rate of lymph node clearance at the renal vein level, perioperative complications, and the number of removed lymph nodes. Quantitative data were analyzed using the t-test, non-normally distributed data using the rank-sum test, and categorical data using Fisher's exact test and the chi-square test, with statistical significance defined as P < 0.05. RESULTS: Among 173 patients, the antegrade group showed higher surgery success (97.5% vs 68.82%), more lymph nodes removed (median 14 vs 7), and less median blood loss. The operation time was shorter in the antegrade group. Postoperative complications like lymphocele and venous thrombosis were lower in the antegrade group. Vascular abnormalities were found in 28.9% of patients, with accessory lumbar vein routing anomaly and accessory renal arteries being most common. CONCLUSIONS: The antegrade approach is feasible, safe, and effective, improving surgical exposure, reducing difficulty without additional instruments or puncture sites, and minimizing organ damage risk. It is effective in achieving better access to the renal vein and removing more para-aortic lymph nodes than the retrograde method. Recognizing and carefully managing the diverse vascular abnormalities in the para-aortic area, including variations in renal arteries, veins, and the inferior vena cava, is essential to reduce intraoperative bleeding and the likelihood of converting to open surgery.

Efficacy of lengthening right renal veins using accompanying gonadal veins in living donor kidney transplantation.

BACKGROUND: Short harvested right renal veins (RV) are quite common in living donor kidney transplantation (KT). This technical difficulty might interfere implanting and increase warm ischemic time. Several techniques to overcome this problem have been applied, including iliac vein transposition, inverted transplant, synthetic graft, saphenous vein… Application of accompanying gonadal vein (GV), which is easily approachable and less time-consuming, has been recently published. This study aims to evaluate its effectiveness and safety. METHODS: Retrospective study on KT using the gonadal vein to lengthen the short right renal vein at Viet Duc University Hospital from April 2019 to April 2022. The following data were gathered: baseline characteristics, vascular imaging in CT scan/after nephrectomy and after reconstruction (mm), reconstruction and surgical time, hospitalization days. The outcomes were determined by kidney function after transplantation (plasma creatinine, creatinine clearance) and related complications. RESULTS: Twenty-five cases with procured right kidney with short RV from the living donor which were reconstructed and lengthened by the accompanying GV were collected. The additional length of RV was 15.9 ± 2.4 mm. Average cold ischemic time, venoplasty time, warm ischemic time were 60.4 ± 8.2, 21.2 ± 5.3, and 38.1 ± 5.6 min, respectively. The average hospital stay was 15.3 ± 3.2 days. Average follow-up time was 31 ± 5.2 months, creatinine clearance was around 60 ml/min after 1 year, no vascular or urologic complications was observed. CONCLUSION: Accompanying GV from a living donor to lengthen short right RV in KT is a feasible, safe, and effective technique.

The effect of retroaortic left renal vein on lumbar osteophytes formation.

PURPOSE: Assess whether a Retroaortic left renal vein (RLRV) affects vertebral osteophyte formation in the lumbar spine, compared to normal anatomy left renal vein. METHODS: We conducted a retrospective case-control study. Computed tomography (CT) scans of individuals with a RLRV (study group) were compared to age- and gender-matched normal anatomy CT scans (control group). L1 to L4 vertebral levels were appreciated for: left renal vein level, osteophyte presence and the aorta-vertebral distance (AVD) at the left renal vein level. Univariate analyses were conducted using Chi-square test and Fisher's test for categorical variables, and Student's t-test for continuous variables. Logistic regression was used for multivariate analyses. RESULTS: A total of 240 patients were included in the study - equally distributed between the study and control groups. Normal anatomy left renal veins traversed the spine only at the L1 and L2 levels. RLRVs traversed the spine in all L1-L4 levels, mostly at the L3 and L2. Osteophyte prevalence at the level of left renal vein was significantly higher in the study group, compared with the control group [OR 2.54, P = 0.01]. Mean AVD was greater in the study group [9.2 mm ±3.6 mm Vs. 3.5 mm ± 2.6 mm, P < 0.001]. Increased AVD was found to be associated with a higher chance of osteophyte presence at the level of the left renal vein [OR 1.282, P = 0.025]. CONCLUSIONS: Osteophytes are more prevalent at the level of the RLRV variant compared to the normal anatomy. Furthermore, the RLRV is characterized by a lower lumbar level compared to the normal anatomy. CLINICAL RELEVANCE STATEMENT: This anatomic variation could assist in further understanding of osteophyte formation.

Multi-omics analysis of renal vein serum with Ischemia-Reperfusion injury.

BACKGROUND: Acute kidney injury (AKI) is frequently caused by renal ischemia-reperfusion injury (IRI). Identifying potential renal IRI disease biomarkers would be useful for evaluating AKI severity. OBJECTIVE: We used proteomics and metabolomics to investigate the differences in renal venous blood between ischemic and healthy kidneys in an animal model by identifying differentially expressed proteins (DEPs) and differentially expressed protein metabolites (DEMs). METHODS: Nine pairs of renal venous blood samples were collected before and at 20, 40, and 60 min post ischemia. The ischemia time of Group A, B and C was 20,40 and 60 min. The proteome and metabolome of renal venous blood were evaluated to establish the differences between renal venous blood before and after ischemia. RESULTS: We identified 79 common DEPs in all samples of Group A, 80 in Group B, and 131 in Group C. Further common DEPs among all three groups were Tyrosineprotein kinase, GPR15LG, KAZALD1, ADH1B. We also identified 81, 64, and 83 common DEMs in each group respectively, in which 30 DEMs were further common to all groups. Bioinformatic analysis of the DEPs and DEMs was conducted. CONCLUSION: This study demonstrated that different pathological processes occur during short- and long-term renal IRI. Tyrosine protein kinase, GPR15LG, Kazal-type serine peptidase inhibitor domain 1, and all-trans-retinol dehydrogenase are potential biomarkers of renal IRI.

Case of Isolated Absence of the Azygos Vein: Evaluation Using Photon-counting Detector CT.

The isolated absence of the azygos vein was incidentally found on computed tomography (CT) examination in a 60-year-old female. The exact anomaly can be evaluated on high-resolution images of 0.4-mm slice thickness with low keV using photon-counting detector CT. The azygos vein, including the azygos arch, was absent, and a mildly dilated hemiazygos vein flowed to the left brachiocephalic vein through the left superior intercostal vein. A hemiazygos vein connected the left renal vein at the level of the first lumbar vertebra. This patient was the second patient to undergo evaluation using volume rendering images. High-resolution maximum-intensity projection images were useful for assessing the anatomy. Radiation dose was decreased compared with that in conventional CT.

Selective venous sampling for secondary hypertension.

Selective venous sampling (SVS), an invasive radiographic procedure that depends on contrast media, holds a unique role in diagnosing and guiding the treatment of certain types of secondary hypertension, particularly in patients who may be candidates for curative surgery. The adrenal venous sampling (AVS), in particular, is established as the gold standard for localizing and subtyping primary aldosteronism (PA). Throughout decades of clinical practice, AVS could be applied not only to PA but also to other endocrine diseases, such as adrenal Cushing syndrome (ACS) and Pheochromocytomas (PCCs). Notably, the application of AVS in ACS and PCCs remains less recognized compared to PA, with the low success rate of catheterization, the controversy of results interpretation, and the absence of a standardized protocol. Additionally, the AVS procedure necessitates enhancements to boost its success rate, with several helpful but imperfect methods emerging, yet continued exploration remains essential. We also observed renal venous sampling (RVS), an operation akin to AVS in principle, serves as an effective means of diagnosing renin-dependent hypertension, aiding in the identification of precise sources of renin excess and helping the selection of surgical candidates with renin angiotensin aldosterone system (RAAS) abnormal activation. Nonetheless, further basic and clinical research is needed. Selective venous sampling (SVS) can be used in identifying cases of secondary hypertension that are curable by surgical intervention. Adrenal venous sampling (AVS) and aldosterone measurement for classificatory diagnosis of primary aldosteronism (PA) are established worldwide. While its primary application is for PA, AVS also holds the potential for diagnosing other endocrine disorders, including adrenal Cushing's syndrome (ACS) and pheochromocytomas (PCCs) through the measurements of cortisol and catecholamine respectively. In addition, renal venous sampling and renin measurement can help to diagnose renovascular hypertension and reninoma.

Impact of Left Renal Vein Ligation on Renal Function Following En Bloc Resection of Segmental Inferior Vena Cava and Right Kidney.

BACKGROUND: Renal function after left renal vein (LRV) ligation following en bloc resection of segmental inferior vena cava (IVC) and right kidney is understudied. We assessed the impact of LRV ligation on postoperative renal function following en bloc resection of segmental IVC and right kidney. METHODS: We retrospectively reviewed 28 patients who underwent LRV ligation during en bloc resection of segmental IVC and right kidney. Patient demographics, tumor characteristics, intraoperative factors, complications, length of hospital and intensive care unit (ICU) stay, and patient survival were collected. Pre- and postoperative renal function was retrospectively analyzed. RESULTS: Twenty patients underwent robot-assisted surgery and eight patients underwent open surgery. The median operative time was 162 min and estimated blood loss was 350 mL. Ten patients had normal renal function and 12 patients had an initial increase in creatinine but improved gradually. Six patients developed acute renal failure; five patients gradually recovered in 5-32 days after temporary hemodialysis. Renal replacement therapy significantly correlated with maximal anterior-posterior diameter of the LRV (p = 0.001). Complications were observed in 11 cases, four of which were Clavien-Dindo grades I-II. Thirteen patients were alive with no recurrence, nine patients were alive with metastasis, and six cases died during the follow-up period. CONCLUSIONS: LRV ligation following en bloc resection of segmental IVC and right kidney is feasible, with no significant long-term impact on renal function. The maximum anterior-posterior diameter of the LRV is a reliable method for predicting renal replacement therapy in the absence of collateral circulation.

A new notable compression source of left renal vein entrapment: right renal artery.

PURPOSE: To estimate the incidences of left renal vein (LRV) entrapment by right renal artery (RRA), a phenomenon primarily reported as case reports. METHODS: The cross-sectional study consecutively screened renal vessel CT data of 38 (Renal) patients with nephropathy and 305 (Non-renal) patients with peripheral arterial diseases in a teaching hospital in northeast China between November 2018 and March 2023. The LRV compression by adjacent anatomical structures, including but not limited to RRA and multiple compression-related parameters, were investigated through multiplanar analysis of the CT data. RESULTS: The overall LRV entrapment rates by adjacent structures were 41.93% (12/31) and 24.00% (6/25), the rates of RRA-sourced LRV compression 22.58% (7/31) and 20.00% (5/25), and the rates of compression by superior mesenteric artery (SMA) 16.13% (5/31) and 4.00% (1/25) in the Renal and Non-renal groups, respectively, with no significance. The venous segments distal to the RRA-compressed site had a significantly larger transectional lumen area than those of the non-compressed veins in both groups (3.09 ± 1.29 vs. 1.82 ± 0.23, p < 0.001 and 4.30 ± 2.65 vs. 2.12 ± 0.55, p = 0.006; maximum-to-minimum area ratios in Renal and Non-renal groups, respectively). Nearly 80% of RRAs were found arising anteriorly rightwards instead of passing straight to the right. CONCLUSION: RRA-sourced LRV compression was not rare, and its incidence was higher than that of the compression by SMA in both patient cohorts. RRA could be a more common compression source than SMA concerning LRV entrapment. Further investigations involving different populations, including healthy individuals, are needed.

Hemodynamics in nutcracker syndrome: implications for diagnosis.

BACKGROUND: Nutcracker syndrome is a disease characterized by complex symptoms, making its diagnosis challenging and often delayed, often resulting in a painful experience for the patients. OBJECTIVE: This study aimed to investigate the pathogenesis of nutcracker syndrome through the perspective of hemodynamics by simulating blood flow with varying compression degrees of the left renal vein. METHODS: 3D patient-specific vascular models of the abdominal aorta, superior mesenteric artery and left renal vein were constructed based on CT images of patients suspected of having nutcracker syndrome. A hemodynamic simulation was then conducted using computational fluid dynamics to identify the correlation between alterations in hemodynamic parameters and varying degrees of compression. RESULTS: The study indicated the presence of an evident gradient in velocity distribution over the left renal vein with relatively high degrees of stenosis (α ≤ 50°), with maximum velocity in the central region of the stenosis. Additionally, when the compression degree of the left renal vein increases, the pressure distribution of the left renal vein presents an increasing number of gradient layers. Furthermore, the wall shear stress shows a correlation with the variation of blood flow velocity, i.e., the increase of wall shear stress correlates with the acceleration of the blood flow velocity. CONCLUSIONS: Using computational fluid dynamics as a non-invasive instrument to obtain the hemodynamic characteristics of nutcracker syndrome is feasible and could provide insights into the pathological mechanisms of the nutcracker syndrome supporting clinicians in diagnosis.

Surgical Management of Wilms Tumors with Intravenous Extension: A Multicenter Analysis of Clinical Management with Technical Insights.

BACKGROUND: About 5% of Wilms tumors present with vascular extension, which sometimes extends to the right atrium. Vascular extension does not affect the prognosis, but impacts the surgical strategy, which is complex and not fully standardized. Our goal is to identify elements of successful surgical management of Wilms tumors with vascular extensions. PATIENTS AND METHODS: A retrospective study of pediatric Wilms tumors treated at three sites (January 1999-June 2019) was conducted. The inclusion criterion was the presence of a renal vein and vena cava thrombus at diagnosis. Tumor stage, pre and postoperative treatment, preoperative imaging, operative report, pathology, operative complications, and follow-up data were reviewed. RESULTS: Of the 696 pediatric patients with Wilms tumors, 69 (9.9%) met the inclusion criterion. In total, 24 patients (37.5%) had a right atrial extension and two presented with Budd-Chiari syndrome at diagnosis. Two died at diagnosis owing to pulmonary embolism. All patients received neoadjuvant chemotherapy and thrombus regressed in 35.6% of cases. Overall, 14 patients had persistent intra-atrial thrombus extension (58%) and underwent cardiopulmonary bypass. Most thrombi (72%) were removed intact with nephrectomy. Massive intraoperative bleeding occurred during three procedures. Postoperative renal insufficiency was identified as a risk factor for patient survival (p = 0.01). With a median follow-up of 9 years (range: 0.5-20 years), overall survival was 89% and event-free survival was 78%. CONCLUSIONS: Neoadjuvant chemotherapy with proper surgical strategy resulted in a survival rate comparable to that of children with Wilms tumors without intravascular extension. Clinicians should be aware that postoperative renal insufficiency is associated with worse survival outcomes.

Robotic Renal Vein Bypass: A Novel Technique for Treating a Challenging Case of Nutcracker Syndrome.

This case report highlights the successful application of a robotic-assisted surgical approach in managing Nutcracker syndrome. The patient, a 36-year-old female presented with severe symptoms and underwent robotic left renal vein transposition after failing conservative management. The procedure was performed through a minimally invasive approach utilizing the Da Vinci robotic system™ which offers enhanced visualization and precision. However, challenges arose during the renal vein anastomosis due to tension and poor flow through the transposition, requiring two revisions with a bovine pericardial patch. Ultimately, an 8 mm ringed PTFE bypass was anastomosed from the distal left renal vein to the Inferior Vena Cava. Despite these challenges, the patient experienced a successful outcome with complete symptom resolution of this complicated pathology.