A Rare Case of Iliac Saccular Aneurysm Communicating with a Transplant Renal Artery.

BACKGROUND Isolated iliac aneurysms are rare. Although they grow very slowly, they can rupture when large enough. Rarely, they rupture into an adjacent organ, such as the colon, the bladder, or even an adjacent vein. Cases of aneurysms rupturing into or communicating with an adjacent vein, leading to an arteriovenous fistula, have been reported. However, reports of aneurysms that rupture and communicate with another adjacent artery have not been found in the literature. CASE REPORT A 52-year-old man who underwent a renal transplantation in the left iliac fossa 21 years ago was admitted for chronic left lower abdominal pain that began 1 year ago. He did not have a history of any invasive procedures or severe trauma after the renal transplantation. Duplex ultrasound showed an oval-shaped hypoechoic structure adjacent to the left external iliac artery (EIA), with a swirling motion of blood flow inside. Computed tomography angiography showed an aneurysm of the left EIA, with a size of 35×34×47 mm, closely adjacent to or even communicating with the transplant renal artery (TRA). There was calcification in the aneurysm wall, without surrounding hematoma. The aneurysm was considered to be a true aneurysm, not a pseudoaneurysm. Endovascular therapy was performed. Digital subtraction angiography confirmed the communication between the aneurysm and the TRA. After the EIA was reconstructed with a covered stent, no leakage was demonstrated; however, contrast still flowed into the aneurysm though the TRA. A second covered stent graft was implanted in the TRA. Subsequently, the aneurysm was successfully excluded. CONCLUSIONS The pathogenesis of this strange aneurysm communicating with another adjacent artery is not well established. Stenting of multiple arteries was needed to treat this aneurysm.

Renal arterial resistive index as a prognostic marker in lupus nephritis patients.

INTRODUCTION: Lupus nephritis (LN) is known to be one of the most serious complications of SLE and it is a major predictor of poor prognosis. Despite the improvement in understanding the pathophysiology of lupus nephritis and greater improvement in diagnostic approaches, lupus nephritis patients have poorer outcomes. OBJECTIVES: Study the relation between renal resistive index (RRI) and renal function and histopathological parameters in lupus nephritis (LN) patients. Also to investigate the usefulness of RRI in predicting response to treatment. PATIENTS AND METHODS: This study included 126 patients who were split into two groups (group 1: 101 LN patients and group 2: 25 SLE patients without renal affection); and 100 healthy controls (group 3). The RRI was measured for all participants through a colored Doppler ultrasound examination. LN patients underwent renal biopsy and received their therapy and were followed up for 6 months. RESULTS: The RRI was significantly greater in the LN group (mean±SD; 0.64±0.07) than in SLE patients without nephritis (0.5884±0.04) (P<0.0001). The RRI was greater in LN class IV (P<0.0001). RRI significantly correlated with the chronicity index (r=0.704, P<0.0001), activity index (r=0.310, P=0.002), and serum creatinine (r=0.607, P<0.0001) and negatively correlated with eGFR (r=-0.719, P<0.0001). Almost eighty-five percent (84.8%) of LN patients responded to induction therapy. RRI was significantly greater in the nonresponder group (mean±SD, 0.73±0.02) than that in the responder group (0.63±.07) (P<0.0001). All non-responders to induction therapy while only 29.8% of responders had an RRI of ˃0.7. RRI, according to regression analysis was a significant predictor of response to treatment in LN patients. CONCLUSION: RRI was significantly greater in the LN group and significantly correlated with kidney function and histopathological parameters. RRI can predict response to induction therapy in LN patients.

Case report: A case of renal vessel rupture caused by severe vomiting in early pregnancy.

OBJECTIVE: Spontaneous renal vessel rupture is a rare clinical emergency. However, pregnancy symptoms and signs are not obvious, and the limited examination methods obscure the observation. Thus, early renal rupture is challenging to detect, leading to misdiagnosis and poor prognosis. This paper aims to improve clinicians' understanding of this disease and reduce the rate of clinical misdiagnosis. PATIENT CONCERNS: The patient, aged 23 and 11 weeks pregnant, developed severe right lumbar and abdominal pain for 14 hours after severe nausea, vomiting, and paroxysmal intensification. Color ultrasound of the urinary system at another hospital revealed right kidney stones and right ureter dilation. Thus, the patient came to our hospital for treatment. DIAGNOSES: Spontaneous renal vessel rupture. INTERVENTIONS: In this case, the diagnosis of spontaneous renal vascular rupture and hemorrhage was confirmed. Following conservative treatment such as fluid replenishment, blood transfusion, and hemostasis, the patient was given an emergency renal artery embolization due to unstable hemodynamics during treatment and poor conservative treatment effect. OUTCOMES: Nephrectomy was performed after 1-week follow-up for renal necrosis. LESSONS: To avoid missed diagnosis and misdiagnosis, patients with abdominal pain caused by severe vomiting during pregnancy must be closely monitored. Additionally, treatment should be considered individually to ensure the safety of both mother and child. Therefore, spontaneous renal vessel rupture should be considered as the differential diagnosis.

Robot-assisted Partial Nephrectomy With Selective Artery Clamping for Renal Cell Carcinoma in Horseshoe Kidney.

BACKGROUND: Robot-assisted partial nephrectomy (RAPN) has become the standard treatment for small renal tumors, including highly complex cases. However, applying RAPN to renal tumors in the horseshoe kidney (HSK) is clinically challenging due to malformations and complex blood supply. Herein, we present two cases of RAPN in patients with HSK treated using selective artery clamping methods. CASE REPORTS: A 61-year-old male with a 15 mm renal tumor located on the upper pole of the right HSK was referred to our Department. The patient underwent RAPN via the transperitoneal approach, following a three-dimensional computed tomography (3D-CT) assessment. Additionally, before surgery, we confirmed which renal arteries would be clamped in surgery by examining the kidney regions supplied by each renal artery. The second patient referred to our Department, a 45-year-old male, had a 46 mm renal tumor located on the isthmus of the HSK. His tumor received blood supply from two renal arteries, with the bilateral collecting systems converging and forming a ureter on 3D-CT. The patient underwent RAPN through an intraperitoneal approach in the semi-lateral position, with port placement lower than in standard RAPN. Pathological examinations revealed clear-cell renal cell carcinoma with negative surgical margins in both cases. Both patients had no recurrences or metastases at 53 and 13 months post-surgery, respectively. CONCLUSION: We present cases successfully treated with RAPN with selective artery clamping methods for HSK using 3D-CT without encountering complications, even in isthmus tumors.

Impact of Breathing Control Training Program on sonographic quantification of abdominal vasculature.

OBJECTIVES: To compare vascular scanning parameters (vessel diameter, peak systolic velocity, end-diastolic velocity, and resistive index) and scanning time before and after breathing control training program for selected abdominal vessels. METHODS: This study was pre and post quasi-experimental. The researchers designed a breathing training program that gives participants instructions through a video describing breathing maneuvers. Data were collected at the ultrasound laboratory/College of Health and Rehabilitation Sciences in Princess Nourah bint Abdul Rahman University, Riyadh, Saudi Arabia from January 2023 to November 2023. About 49 volunteers at the university participated in the study. Scanning was performed two times for the right renal artery, upper abdominal aorta, inferior vena cava, and superior mesenteric artery. Scanning time was measured before and after the program as well. A paired sample t-test was used to compare the parameters means and time before and after the program. RESULTS: The program had a significant effect on the following parameters: right renal artery peak systolic velocity (p=0.042), upper abdominal aortic peak systolic velocity, and resistive index (p=0.014, p=0.014 respectively), superior mesenteric artery and inferior vena cava diameters (p=0.010 and p=0.020). The scanning time was reduced significantly (p<0.001). CONCLUSION: The breathing training program saves time and improves ultrasound measurement quality. Hospitals and health centers should consider the importance of breathing control training programs before abdominal scanning.

Fibromuscular dysplasia of the renal arteries: what do we know in 2024? / Dysplasie fibromusculaire des artères rénales : que savons-nous en 2024 ?

Fibromuscular dysplasia (FMD) is a rare nonatherosclerotic, noninflammatory vascular disease affecting mostly renal and carotid arteries and is the second most frequent cause of renal artery stenosis. The symptomatology is dominated by arterial hypertension due to the frequent involvement of the renal arteries and depends on the location of the lesions. Most of the cases are middle-aged women of Caucasian origin. There are two subtypes based on angiographic aspect: multifocal FMD (80% of the cases) and focal FMD (rarer with a more balanced sex ratio). Angioplasty of the renal arteries is generally disappointing with less than 50% cure of hypertension. It appears necessary to improve our knowledge of the FMD and to optimize the selection of eligible patients for revascularization with transdisciplinary collegial therapeutic decision.

La dysplasie fibromusculaire (DFM) est une maladie rare caractérisée par des sténoses segmentaires non artérioscléreuses, non inflammatoires, des artères de moyens calibres, touchant surtout les artères rénales et les carotides. Elle constitue la seconde cause de sténoses des artères rénales. La symptomatologie dépend de la localisation des lésions et est dominée par l'hypertension artérielle (HTA) en raison de l'atteinte fréquente des artères rénales. Cette pathologie touche majoritairement les femmes caucasiennes d'âge moyen. Il en existe deux sous-types, basés sur l'aspect angiographique : la DFM multifocale (80 % des cas) et la DFM focale (plus rare, sex ratio plus équilibré). Les résultats des prises en charge interventionnelles s'avèrent globalement décevants avec moins de 50 % de guérison de l'HTA. Il est nécessaire d'améliorer nos connaissances sur la physiopathologie de la DFM et d'optimiser la sélection des patients éligibles à une revascularisation par une prise de décision thérapeutique collégiale, en réunion de concertation pluridisciplinaire.

Overview of the 2023 FDA Circulatory System Devices Advisory Panel meeting on the Recor Paradise Ultrasound-Based Renal Denervation System.

Hypertension continues to be a prominent, avoidable factor contributing to major vascular issues on a global scale. Even with lifestyle adjustments and more aggressive medical treatments, maintaining optimal blood pressure levels remains challenging. This challenge has driven the emergence of device-oriented approaches to address hypertension. To assess the safety and efficacy of the Recor Paradise Ultrasound Renal Denervation System, the Circulatory System Devices Panel was convened by the US Food and Drug Administration (FDA). This manuscript provides a condensed overview of the information put forth by the sponsor and the FDA, along with an account of the considerations and conversations that took place during the meeting.

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.

Deep-learning-based sampling position selection on color Doppler sonography images during renal artery ultrasound scanning.

Accurate selection of sampling positions is critical in renal artery ultrasound examinations, and the potential of utilizing deep learning (DL) for assisting in this selection has not been previously evaluated. This study aimed to evaluate the effectiveness of DL object detection technology applied to color Doppler sonography (CDS) images in assisting sampling position selection. A total of 2004 patients who underwent renal artery ultrasound examinations were included in the study. CDS images from these patients were categorized into four groups based on the scanning position: abdominal aorta (AO), normal renal artery (NRA), renal artery stenosis (RAS), and intrarenal interlobular artery (IRA). Seven object detection models, including three two-stage models (Faster R-CNN, Cascade R-CNN, and Double Head R-CNN) and four one-stage models (RetinaNet, YOLOv3, FoveaBox, and Deformable DETR), were trained to predict the sampling position, and their predictive accuracies were compared. The Double Head R-CNN model exhibited significantly higher average accuracies on both parameter optimization and validation datasets (89.3 ± 0.6% and 88.5 ± 0.3%, respectively) compared to other methods. On clinical validation data, the predictive accuracies of the Double Head R-CNN model for all four types of images were significantly higher than those of the other methods. The DL object detection model shows promise in assisting inexperienced physicians in improving the accuracy of sampling position selection during renal artery ultrasound examinations.

Value of ultra-high b-value diffusion-weighted imaging for the evaluation of renal ischemia-reperfusion injury.

To explore the feasibility of ultra-high b-value diffusion-weighted imaging (ubDWI) in assessment of renal IRI. Thirty-five rabbits were randomized into a control group (n = 7) and a renal IRI group (n = 28). The rabbits in the renal IRI group underwent left renal artery clamping for 60 min. Rabbits underwent axial ubDWI before and at 1, 12, 24, and 48 h after IRI. Apparent diffusion coefficient (ADCst) were calculated from ubDWI with two b-values (b = 0, 1000 s/mm2). Triexponential fits were applied to calculate the pure diffusion coefficients (D), perfusion-related diffusion coefficient (D⁎), and ultra-high ADC (ADCuh). The interobserver reproducibility were evaluated. The repeated measurement analysis of variance and Spearman correlation analysis was used for statistical analysis. The ADCst, D, and ADCuh values showed good reproducibility. The ADCst, D, and D⁎ values of renal Cortex (CO) and outer medulla (OM) significantly decreased after IRI (all P < 0.05). The ADCuh values significantly increased from pre-IRI to 1 h after IRI (P < 0.05) and significantly declined at 24 h and 48 h after IRI (all P < 0.05). ADCuh was strongly positively correlated with AQP-1 in the renal CO and OM (ρ = 0.643, P < 0.001; ρ = 0.662, P < 0.001, respectively). ubDWI can be used to non-invasively evaluate early renal IRI, ADCuh may be adopted to reflect AQP-1 expression.

Double kiss mini-crush technique to treat complex recurrent renal artery in-stent restenosis.

The double-kiss mini-crush (DKMC) technique has been successfully deployed in the past for the treatment of complex coronary lesions even for left main lesions. Our case report consists of a proof-of-principle that the DKMC technique can be successfully translated as well to the field of complex renal artery lesions. Insightful thinking out-of-the "coronary" box in concert with skillful off-label application of coronary stenting procedures may open the gate for unprecedented opportunities for the treatment of difficult-to-tackle in-stent restenosis in the renal circulation.

Latest evidence on chimney endovascular repair of abdominal aortic aneurysms and the renal artery angulation pitfall.

This article summarizes the key findings in literature up to date on the endovascular treatment of complex abdominal aortic aneurysms (AAAs) employing the chimney technique. Additionally, an unexplored pitfall is described regarding the target vessel angulation. Although balloon-expandable covered stents present more favorable configuration in downward-oriented target vessels, transverse and upward-oriented target vessels may benefit from other endovascular techniques imploring careful case planning and further investigation on the topic.

A Qualitative Systematic Review of Endovascular Management of Renal Artery Aneurysms.

PURPOSE: To perform a qualitative systematic review of endovascular management of renal artery aneurysms (RAAs). MATERIALS AND METHODS: A comprehensive electronic search of PubMed, MEDLINE, Embase, Google Scholar, and Cochrane databases from 2000 to 2022 was performed using the search terms "renal artery," "aneurysm," and "endovascular." Means of outcome measures were calculated with a primary end point focused on RAA-related mortality and rupture. Secondary end points included reintervention rate and renal infarction. RESULTS: Twenty-six, single-center, retrospective, observational studies were included. There were 454 RAAs treated in 427 patients using endovascular techniques. Mean age was 53.8 years, with a female predominance (62%). A variety of endovascular treatments of RAA were used with excellent technical success (96%), renal parenchymal preservation, and a low rate of moderate/severe adverse events (AEs). Primary coil embolization was the most commonly used technique (44.7%). There was an overall AE rate of 22.9%, of which 6.7% were moderate/severe and there was 0% periprocedural mortality. The most common AE was renal infarction (49 patients, 11.5%); however, renal function was preserved in 84% of patients. Nephrectomy rate was 0.4%. Computed tomography (CT) angiography was the most common imaging follow-up modality used in 72% of studies. Only 9 studies (34%) reported anticoagulant use. Although the risk of delayed aneurysm reperfusion warrants clinical and imaging surveillance, relatively few patients (3%) required reintervention in this cohort. CONCLUSIONS: Endovascular management of RAA is a technically feasible treatment option with low rates of AEs and reintervention. The present study highlights the techniques available for interventional radiologists, a need for standardization of AE reporting, anticoagulation therapy, and follow-up imaging.

Doppler Ultrasound of the Renal Vasculature.

Ultrasound is the first-line imaging modality used in patients with suspected renovascular disease. Common indications include renovascular hypertension and unexplained renal dysfunction. We review the ultrasound imaging findings of various pathologies involving the renal vessels, including the renal arteries (atherosclerotic stenosis, fibromuscular dysplasia, dissection, arteriovenous fistula, and aneurysm) and veins (tumor and bland thrombus as well as vascular compression syndromes). The current role of renal artery stent placement for atherosclerotic stenosis is also discussed.

Effectiveness of contrast-enhanced duplex ultrasound for detecting renal artery stenosis: A systematic review.

PURPOSE: Contrast-enhanced duplex ultrasound (CEUS) might be a useful tool to diagnosing renal artery stenosis (RAS). We amalgamated and reviewed the evidence assessing the diagnostic accuracy of CEUS on detecting RAS compared to angiography. METHODS: This preregistered systematic review included studies that compared the presence of RAS via CEUS with angiography. Sources were searched in November 2022 and included Scopus, EMBASE, MEDLINE, CINAHL, and Academic Search Premier (n = 1717). The Quality Assessment of Diagnostic Studies 2 tool assessed study quality. Results are presented narratively. RESULTS: The studies included (n = 11) had a total of 447 unique participants (193 females) and average age of 56 ± 9 years. Five of eleven studies investigated CEUS using SonoVue contrast agent and reported an average accuracy (91% ± 2%), sensitivity (91% ± 3%), specificity (90% ± 5%), negative predictive value (86% ± 6%), and positive predictive value (94% ± 1%) with all values >80%. The accuracy of CEUS using other types of contrast agent (n = 6), including Levovsit (n = 3/6), Definity (n = 1/6), perfienapent emulsion (n = 1/6), and perfluorocarbon-exposed sonicated dextrose albumin (n = 1/6) was mixed. These studies detected an average accuracy of 91 ± 11% (n = 2/3% > 80%), sensitivity of 98% ± 4%, (n = 3/3% > 80%), and specificity of 86% ± 10% (n = 2/3% > 80%). Included studies had generally low risk of bias and applicability concerns except for unclear flow and timing (n = 7/11) and applicability of patient selection (n = 4/11). CONCLUSION: Despite being limited by the heterogeneity of included studies, our review indicates a high overall diagnostic accuracy for CEUS to detect RAS compared to angiography, with the largest evidence-base for SonoVue contrast. Radiologists and hospital decision makers should consider CEUS as an acceptable alternative to angiography.

Renal Artery Coil Embolization as an Endovascular Approach for Establishing a Rabbit Model of Chronic Kidney Disease.

PURPOSE: To investigate the safety and feasibility of renal artery coil embolization for establishing chronic kidney disease (CKD) in rabbits. MATERIALS AND METHODS: Ten male adult New Zealand rabbits underwent renal artery coil embolization. Initially, the main renal artery on 1 side was completely embolized, followed by embolization of approximately two-thirds of the primary branches of the contralateral renal artery 1 week later. Four rabbits were randomly chosen for sacrifice at 4 weeks after embolization, whereas the remaining 6 were sacrificed at 8 weeks after embolization. The assessment encompassed the animals' general condition, angiography, biochemical parameters, inflammatory markers, and histopathological examination of the kidneys and hearts. RESULTS: Four weeks after embolization, serum creatinine level showed a substantial increase (2.4 mg/dL [SD ± 0.6]; P = .009 vs baseline), with a subsequent 4.12-fold elevation at 8 weeks after embolization (4.9 mg/dL [SD ± 1.4]; P < .001 vs baseline). Additionally, considerable increases in serum blood urea nitrogen, calcium, and potassium ions were observed at 8 weeks after embolization (58.3 mg/dL [SD ± 19.0]; P < .001 vs baseline; 23.1 mg/dL [SD ± 4.4]; P < .001 vs baseline; and 6.3 mEq/L [SD ± 0.7]; P < .001 vs baseline, respectively). The completely embolized kidney exhibited notable atrophy, severe fibrosis, and cortical calcification, whereas the contralateral partially embolized kidney displayed compensatory hypertrophy, along with glomerulosclerosis, tubular dilation, tubular casts, and interstitial fibrosis. CONCLUSIONS: Renal artery coil embolization proved to be effective and safe for establishing a CKD model in rabbits.

The prevalence of accessory renal arteries in sudanese population in Khartoum State: a cross-sectional CT study from 2017 to 2020.

BACKGROUND: Renal artery variations are clinically significant due to their implications for surgical procedures and renal function. However, data on these variations in Sudanese populations are limited. This study aimed to determine the prevalence and characteristics of renal artery variations in a Sudanese population. METHODS: A cross-sectional retrospective study was conducted in Khartoum state from October 2017 to October 2020. A total of 400 Sudanese participants who underwent abdominal CT scans were included. Data on demographic characteristics, kidney measurements, and renal vasculature were collected and analyzed using descriptive statistics and inferential tests. RESULTS: The mean age of participants was 46.7 ± 18 years, with a nearly equal gender distribution. Overall, renal artery variations were present in 11% of participants, with accessory renal arteries observed in 6% of the study population. Among those with accessory vessels, 50% were on the right side, 29.2% on the left, and 20.8% bilateral, distributed across hilar 29.2%, lower polar 29.2%, and upper polar 41.7% regions. No significant associations were found between accessory renal arteries and age or gender (p-value > 0.05). However, participants with accessory renal arteries exhibited significantly narrower width 5.0 ± 1.4 than those with no with accessory renal arteries 5.8 ± 1.1 (p-value 0.002) Early dividing renal arteries were found in 5% of participants, with nearly half being bilateral. No significant associations were found between the presence of early dividing renal arteries and demographic or renal measurements (p-value > 0.05). CONCLUSION: This study provides valuable insights into the prevalence and characteristics of renal artery variations in a Sudanese population. The findings contribute to our understanding of renal anatomy in this demographic and can inform clinical practice and surgical planning, particularly in renal transplantation and other renal procedures.