Hilar Renal Artery Research Articles

Hilar Renal Artery Aneurysms Repaired Ex-Vivo with Autotransplantation

Renal artery aneurysms have an incidence of 0.1% with a rupture rate of 3-5% and mortality rate of less than 10% when excluding pregnant patients (1). Majority are found incidentally with no symptoms. Complex renal artery aneurysms in the hilum or at branching points with no endovascular repair options require open repair. Open repair options consist of in-situ repair or ex-vivo repair with autotransplantation.

Bilateral extra‐renal pelvises and calyxes with additional renal blood vessel variations identified in a single prosected medical school donor body

While there are relatively commonly observed, reported anatomical variations associated with the posterior abdominal wall, especially with the kidneys, we report here over a dozen variations in one prosected medical school donor body (Caucasian, male, age 87, cause of death: sepsis). These variations could contribute significantly to negative outcomes, especially in surgical procedures. During a routine dissection, we found bilateral extra‐renal pelvises. In the right kidney, there were two extra‐renal major calyxes, and five extra‐renal minor calyxes (two extra‐renal minor calyxes from the superior major calyxes, and three extra‐renal minor calyxes from inferior major calyxes). In the left kidney, there were four extra‐renal major calyxes and two extra‐renal minor calyxes off the most inferior major calyx. In addition, we found four venous variations and four arterial anomalies including one in a major artery. Namely, there were bilateral accessory renal veins found at the hilum that drained into the posterior aspect of the inferior vena cava. There was an additional accessory left renal vein that drained into the left renal vein, at the junction of the left testicular and left suprarenal veins. There was also a left lumbar vein that drained into one of the accessory left renal veins. Regarding the arterial supply to the kidneys, there were two polar right renal arteries directly off the abdominal aorta in addition to two long hilar right renal arteries, and three left hilar renal arteries that branched individually from the abdominal aorta. Finally, there was a long left common iliac artery compared to the right common iliac artery. Anatomical variations within patients can be of no significance or can turn a routine surgical procedure into a hazardous process if unrecognized at the time of intervention. Further documentation of such anatomical variations in prosected donor bodies can further inform surgeons for the need for imaging prior to various surgical procedures.

Evaluation of Diameter of Main Hilar Renal Artery to Predict the Presence of Supplementary Renal Artery by Contrast-enhanced MDCT: A Retrospective Study from in Northern India

Introduction: Accessory renal arteries are non anastomotic end arteries that correspond to a single renal artery’s segmental branch. It is the most common anatomic variation of renal artery, with an incidence ranging from 8.7% to 75.7%. Aim: To determine the normal reference range of diameter of the main hilar renal artery in presence or absence of supplementary renal arteries and using contrast-enhanced Multidetector Computerized Tomography (MDCT) in North Indian population. Materials and Methods: This retrospective study was conducted in the Department of Anatomy in collaboration with the Department of Radiodiagnosis at Santosh Medical College and Hospital, Ghaziabad and Dr. O.P Gupta Imaging Centre, Meerut, Uttar Pradesh, India, from April 2019 to October 2021. Data analysis was done from November 2021 to December 2021. Contrast-enhanced MDCT scan images were reviewed for measurement of the diameter of main hilar and supplementary renal artery. A total of 108 patients were recruited through consecutive sampling. The diameter of the main hilar and supplementary renal artery on each side was measured at the site of origin from the abdominal aorta with the help of an electronic calliper in axial view of MDCT images. The mean differences among the groups with and without supplementary renal artery were evaluated using the student’s t-test. Results: The mean diameter of the main hilar renal artery in the absence of the supplementary renal arteries on the right and left side were 5.99±1.13 mm and 6.07±1.25 mm respectively.The mean diameter of the main hilar renal artery with supplementary renal arteries on the right side was 5.11±1.096 mm and on the left was 5.18±1.08. The mean diameter of the main hilar renal artery was smaller in kidneys with a supplementary renal artery than in those without a supplementary renal artery, statistically significant difference was evaluated (p-value<0.001 on the right and left side). Conclusion: The diameter of the main hilar renal artery can indicate whether supplemental renal arteries exist or not.

Results of Surgical Repair of Hilar Renal Artery Aneurysm to Preserve Renal Blood Flow.

Objective: Surgical indications and procedures for hilar renal artery aneurysm (HRAA) are controversial in terms of invasiveness and feasibility. Catheter treatment is minimally invasive but leads to renal dysfunction due to renal infarction. This study aims to investigate the results of surgical repair of HRAA.Method: Fourteen patients (58.7±11.6 years old, 7 male) who underwent surgical repair of HRAA were retrospectively reviewed. Nine patients (64%) developed HRAA in the right renal artery, and the mean maximum aneurysmal diameter was 25.9±10.3 mm. HRAA was exposed via the extraperitoneal approach. HRAA was resected completely, and reconstruction of renal arteries was performed by direct closure in two, direct anastomosis in nine, and interposition of saphenous vein graft in three patients.Results: The average operation and renal ischemic times were 186±49 and 35±16 min, respectively. No operative death occurred, and postoperative renal function at the time of discharge had not deteriorated (creatinine, 0.74±0.15 mg/dl). During the follow-up periods (4.7±5.1 years), there was no death, no new introduction of hemodialysis, and no recurrence of renal artery aneurysm.Conclusion: Surgical repair of HRAA remains a valid option because of its operative safety, preservation of renal function, and long-term feasibility and patency.

Clinical application of renal autotransplantation in complex urological diseases

Objective: To summarize the experience of renal autotransplantation for severe iatrogenic proximal ureteral damage and renal artery aneurysms in eight patients and to explore the clinical application value of renal autotransplantation. Methods: Two patients of renal artery aneurysms and six patients of severe iatrogenic proximal ureteral damage between January 2010 and March 2018 in our center were retrospectively reviewed. Results: The procedures of eight cases were successful, with immediate return of renal function in the patients. The warm ischemia time was (3±1) minutes, the total operation time was (340±164) min, and the estimated blood loss was (180±60) ml, respectively. For renal artery anastomosis, six patients of severe iatrogenic proximal ureteral damage received end-to-end anastomosis between the internal iliac artery and renal artery, and two patients of renal artery aneurysms were treated with renal artery and internal iliac artery for reconstruction, then end-to-side anastomosis to recipien external iliac artery. A direct ureterovesical anastomosis was performed in seven patients, one patient was received pyeloureteroplasty. No serious complications of blood vessel and ureter were found during perioperative and long-term follow-up. All cases follow-up hitherto have normal renal function and blood pressure. Conclusions: Renal autotransplantation can be appropriate for patients with proximal ureteral loss and complex hilar renal artery aneurysms. In addition, it is able to protect renal functions to the most extent and provides a surgical alterative for complex renal diseases.

VARIATIONS OF RENAL ARTERY: A CADAVERIC STUDY

Introduction: Renal arteries are the lateral branches of abdominal aorta, which vary in number, origin and course. The aim of this study was to document the incidence of renal artery variations in number and position, which can be advantageous to urosurgeons and imaging experts. Material & Methods: The study was conducted on 36 formalin fixed embalmed cadavers. The renal artery variations were observed and noted during routine posterior abdominal wall dissection for medical undergraduates in dissection hall in the Department of Anatomy, BRD Medical College Gorakhpur and IMS, BHU Varanasi. Results: We observed accessory renal artery (ies) in 30.56% of cases with unilateral incidence in 27.78% and bilateral in 2.67% cases. Accessory hilar renal artery (ies) were observed in 16.68% and accessory polar renal artery (ies) in 13.89% cases. Accessory arteries were more common on left (16.68%) than on the right side (11.12%). Inferior polar arteries were more common than superior polar arteries. Conclusion: Knowledge of the variations of renal artery is of immense importance to the urosurgeons during renal transplantation, partial nephrectomy, laparoscopic surgery and angiographic interpretation by radiologists.

Symptomatic hilar renal artery aneurysm mimicking renal colic - a word of caution

An adequate and timely diagnosis is crucial in the treatment of renal artery aneurysms during pregnancy since the risk of rupture and its catastrophic consequences are high. Clinical symptoms, laboratory results, and B-mode abdominal ultrasonography may mimic renal colic. In this report, a case of a pregnant 26-year-old woman with a large, symptomatic renal aneurysm is presented. The diagnostic pathway and the treatment are described. Potential pitfalls in the diagnosis are discussed.

The gross anatomy of the renal sympathetic nerves revisited.

Catheter-based renal denervation techniques focus on reducing blood pressure in resistant hypertension. This procedure requires exact knowledge of the anatomical interrelation between the renal arteries and the targeted renal nervous plexus. The aim of this work was to build on classical anatomical studies and describe the gross anatomy and anatomical relationships of the renal arteries and nerve supply to the kidneys in a sample of human cadavers. Twelve human cadavers (six males and six females), age range 73 to 94 years, were dissected. The nervous fibers and renal arteries were dissected using a surgical microscope. The renal plexus along the hilar renal artery comprised a fiber-ganglionic ring surrounding the proximal third of the renal artery, a neural network along the middle and distal thirds, and smaller accessory ganglia along the course of the nerve fibers. The fibers of the neural network were mainly located on the superior (95.83%) and inferior (91.66%) surfaces of the renal artery and they were sparsely interconnected by diagonal fibers. Polar arteries were present in 33.33% of cases and the renal nerve pattern for these was similar to that of the hilar arteries. Effective renal denervation needs to target the superior and inferior surfaces of the hilar and polar arteries, where the fibers of the neural network are present. Clin. Anat. 29:660-664, 2016. © 2016 Wiley Periodicals, Inc.

Multiple variations of the renal and testicular vessels: possible embryological basis and clinical importance

During routine dissection of the abdominal cavity of a 55-year-old African male cadaver, multiple anomalies including renal and testicular vessels were encountered. The right kidney was supplied by three right hilar renal arteries arising from the abdominal aorta at different vertebral levels whereas only one left renal artery supplied the left kidney. On the right three renal veins drained the kidney into the inferior vena cava. In contrast, the left kidney was drained by a single renal vein which received a large primary posterior tributary. The primary posterior tributary had three tributaries from the posterior lumbar region. The right testis had two sources of arterial supply; one from the subcostal artery and another from the abdominal aorta. The left testis was supplied normally by a single testicular artery. The right testis was drained by four testicular veins as follows: one drained into the subcostal vein, the other two drained separately for a longer course and joined shortly before draining into the right main renal vein, the fourth one drained into the anterior aspect of the inferior vena cava at the level of the second lumbar vertebra. On the left, the testicle was drained by two testicular veins which travelled separately from the deep inguinal ring and joined shortly before they drain into the left renal vein. This variation may represent an immature form of complicated development of kidneys and testes. Additionally, emphasis must be put on preoperative vascular examination to avoid surgical complications from variant vessels in this region.

Renal Autotransplant in Patients With Complex Hilar Renal Artery Aneurysms

Renal artery aneurysms are uncommon, with an incidence of 0.01% in the general population. The improvement of radiologic techniques and the increased incidence of abdominal imaging for various indications has resulted in increased detection of asymptomatic renal artery aneurysms. Hilar renal artery aneurysms are a subtype of the disease and constitute management challenges. Here, we report 3 patients with hilar renal artery aneurysms treated with renal autotransplant and review the literature.

Experiences of Renal Transplants From Donors With a Renal Artery Aneurysm After a Laparoscopic Donor Nephrectomy and Ex Vivo Reconstruction of the Renal Artery

Renal artery aneurysms are uncommon, and various surgical options to treat renal artery aneurysms have been described. We report 2 cases of renal transplants from donors with renal artery aneurysm, after resection of aneurysm, and ex vivo renal artery reconstruction. Two women, aged 52 and 45 years, had diagnoses of hilar renal artery aneurysms during evaluation for left flank pain and hematuria. In both cases, radiologic interventions were impossible because of anatomical relations. Both patients were informed of the therapeutic options available, including nephrectomy, autotransplant, and kidney donation. The patients and their families decided on a kidney donation. Renal function test results of both patients satisfied the living-donor selection criteria. The left and right kidney of each patient was removed laparoscopically, and ex vivo resection of the aneurysm and reconstruction of the renal artery was performed under a surgical microscope. The repaired kidneys were successfully transplanted to 2 men, aged 36 and 37 years. In cases of renal artery aneurysms that necessitate treatment, a renal allograft transplant should be considered as a treatment option. It provides safety and benefit to the recipient as well the donor.

Transplantation of a Horseshoe Kidney

Because of the continuing organ shortage, kidneys with atypical anatomy are frequently considered for transplantation. The most common anatomic variation of the kidney is the horseshoe kidney, with an incidence of 1 in 800. These kidneys are frequently accompanied by vascular and urinary tract abnormalities and there has always been a concern for primary nonfunction based on technical failure (1, 2). Discard of potentially usable horseshoe kidneys can occur because of vascular anatomic limitations or injuries. According to a recent report of horseshoe kidneys that were donated within the Eurotransplant region, 27% were discarded immediately and 9.6% were discarded after division. The reason was the complex vascular anatomy in at least 53.8% and 60%, respectively (3). We present a case of whole horseshoe kidney transplantation after extensive vascular reconstruction. A horseshoe kidney from a 52-year-old male deceased donor was accepted at the University of Pittsburgh Medical Center. The cause of death was a cerebrovascular accident. The backtable wedge kidney biopsy showed 10% glomerulosclerosis and mild interstitial fibrosis, arteriosclerosis, and arteriolosclerosis. The horseshoe kidney had been recovered en bloc with the accompanying aorta and inferior vena cava (IVC). The arterial supply to the horseshoe kidney consisted of two right hilar renal arteries connected to the aorta, two left hilar renal arteries that were transected at their common orifice at the aorta, an isthmic artery (previously a branch of the right external iliac artery), and a left superior pole artery transected midway from its aortic origin. Venous drainage consisted of bilateral double renal veins to the IVC. Reconstruction was performed by anastomosis of the hilar arteries to the single orifice at the original site on the aorta, the left superior pole artery to its transected branch, and the isthmus artery to a newly created orifice at the inferior aorta. The superior poles of the aorta and IVC were oversewn (Fig. 1).FIGURE 1.: Arterial vascular reconstruction of horseshore kidney.The recipient was a 63-year-old female with end-stage renal disease secondary to tacrolimus toxicity after lung transplantation. The recipient operation was performed through a standard extraperitoneal approach in the right iliac fossa. Revascularization was accomplished by anastomosis of the inferior IVC and aorta to the external iliac artery and vein, respectively. The ureters were anastomosed to the bladder using separate extravesical ureteroneocystostomies. The cold ischemia and anastomosis times were 34 hr and 35 min, respectively. Both kidneys reperfused entirely. Immunosuppression consisted of induction with daclizumab and maintenance immunosuppression with tacrolimus, mycophenolate mofetil, and prednisone. There were no vascular or ureteral complications. The serum creatinine was 1.6 mg/dL two weeks posttransplantation. Our decision to transplant the whole horseshoe kidney as a single kidney rather than divided into two kidneys was due to the presence of an isthmic artery. Horseshoe kidneys have previously been transplanted successfully with reasonable results. Due to the organ shortage, efforts to overcome the anatomic challenges of horseshoe kidneys are worthwhile. Anthony T. Corcoran Ron Shapiro Liise K. Kayler Department of Surgery University of Pittsburgh Medical Center Pittsburgh, PA

Renovascular Hypertension and Double Renal Arterial Supply Diagnosed by Tc-99m MAG3 Captopril Renography

Renovascular hypertension is the most frequent secondary cause of hypertension (0.5–2%). Captopril renal scintigraphy is safe, noninvasive, and effective in the detection of renovascular hypertension. Positive captopril renography may suggest a cure of hypertension and improvement in renal function with successful renal revascularization. The authors report the case of successful detection of renovascular hypertension by captopril renal scintigraphy in a patient with 2 hilar renal arteries. Revascularization of the stenosed hilar artery was obtained by transluminal angioplasty and stent placement, leading to rapid control of the hypertension.

Cirugía sin arteriografía de los troncos viscerales

Summary Aims The aim of this paper is to describe the advantages and disadvantages of Doppler ultrasound (DUS), computerised tomographic angiography (CTA) and magnetic resonance angiography (MRA) in the study of lesions in the visceral trunks (VT), in comparison with digital subtraction arteriography (DSA), according to the medical literature published to date. Development DUS allows the presence of stenosis in the VT to be detected, with a sensitivity of between 90 and 95% and a specificity of between 85 and 90%. Its main limitations are the variability depending on the operator's experience and on the anatomical characteristics of the patient. CTA is a good test for detecting thepresence of stenoses in the renal arteries and mesenteric trunks (MT), although few comparative studies have been performed on the subject. Its chieflimitations are the inadequate measurement of the degree of stenosis in severe stenoses and the need to use a nephrotoxic contrast. 3D contrast MRA (MRA 3D) seems to be the ideal test in vascular studies with MR. The use of non-ionising radiations andcontrastsfree of nephrotoxic effects are two of the advantages of MRA compared with DSA or CTA. MRA offers a sensitivity of between 88 and 100%, and a specificity of between 71 and 100% in the study of renal arteries. Like CTA, it displays a tendency to overestimate the degree of stenosis. The DUS, CTA and MRA all offer low sensitivity and specificity in the study of arterial lesions in polar arteries and in the hilar renal artery. Conclusions DUS is a sensitive test that is relatively cheap and accurate enough for use as a screening test in the study of stenoses in the VT, but little work has been published in which DUS are employed as a single diagnostic tool to indicate a renal or mesenteric revascularisation. The value of CTA in the study of the renal artery and of the MT will have to be proved by means of double-blind studies that compare it with DUS. Until the appearance of these studies, it must be considered to be a screening test or a technique to complement DUS. MRA is a good test for diagnosing stenosis of the renal artery, with a similar sensitivity and specificity to those of DUS. At the same, it offers the possibility of determining the functional repercussions of the arterial lesion. MRA is also a technique that has obtained similar results to those offered by DUS in the study of the main MT. We will, however, probably have to wait for the results of double-blind tests carried out with large numbers of patients before we can accept MRA as a single diagnostic test in MT lesions.

Pulsed Doppler sonography of the hilar renal artery: Differentiation of obstructive from nonobstructive hydronephrosis in children

Background/Purpose: It is difficult to detect the arcuate or cortical renal arteries when performing pulsed Doppler sonography (PDS) for congenital hydronephrosis. This study was undergone to assess the usefulness of PDS of the hilar renal artery to differentiate obstructive from nonobstructive hydronephrosis. Methods: The authors performed PDS of the hilar renal artery in 80 normal children: 20 aged 0 to 1 months (group I), 20 aged 1 to 12 months (group II), 20 aged 1 to 6 years (group III), and 20 aged 7 to 15 years (group IV). Based on diuretic renography findings, 22 kidneys from 19 children with a ureteropelvic junction (UPJ) stricture were divided into 7 dilated obstructed and 15 dilated nonobstructed kidneys. The peak-systolic velocity (PSV), end-diastolic velocity (EDV), mean average velocity (Vm) and the resistive index (RI = [PSV − EDV]/PSV) were measured at the hilar renal artery. Results: There was a significant difference in the RI of the hilar renal artery between obstructive and nonobstructive hydronephrosis. Conclusion: A pulsed Doppler evaluation of the hilar renal artery is useful for detecting an obstructive UPJ stricture compared with assessing arcuate or cortical renal arteries. J Pediatr Surg 36:416-420. Copyright © 2001 by W.B. Saunders Company.

Operative Repair of Enlarging Hilar Renal Artery Aneurysm

Repair of distal renal artery aneurysms poses a significant threat to kidney salvage despite improved operative techniques described over the past decades. The authors describe the case of a seventy-one-year-old woman who presented with an enlarging right renal artery aneurysm located at the renal hilum involving the lobar arteries. Operative repair was accomplished by excision of the saccular posterior wall and reconstruction with a saphenous vein patch. The ischemia time was thirty-three minutes and her postoperative course was uneventful. She was discharged home on the fifth postoperative day with normal renal function, and the renal arteriogram demonstrated a technically successful operation. They review the current literature, and this case is put into perspective with the natural history, clinical course, and present treatment of renal artery aneurysms.

MR angiography of renal artery stenosis: value of the combination of three-dimensional time-of-flight and three-dimensional phase-contrast MR angiography sequences.

It has been reported and also has been our preliminary experience that many false ostial stenoses are attributable to a loss of signal intensity at the origin of the renal arteries when three-dimensional (3D) phase-contrast MR angiography is used. Our objective was to add a 3D time-of-flight MR angiography sequence to the 3D phase-contrast MR angiography sequence to better analyze the origin of the main renal arteries. We assessed the value of the combination of these two MR angiography sequences for the depiction of renal artery stenosis. Forty-six patients suspected of having renal artery stenosis on the basis of clinical history, physical examination, and laboratory data were prospectively enrolled. Intraarterial digital subtraction angiography findings were available for all patients. Using intraarterial digital subtraction angiography, we considered stenosis to be significant when the vessel was narrowed more than 50%. During MR angiography, half of the data were reconstructed by interpolation to avoid long acquisition times. Total acquisition times were less than 15 min. MR angiography findings were interpreted independently by two radiologists who were unaware of the findings of intraarterial digital subtraction angiography. With 3D phase-contrast MR angiography, any cutoff in signal intensity or any narrowing of the vessel diameter of more than 50% from the renal ostium to the renal hilum was considered to represent significant stenosis. With 3D time-of-flight MR angiography, our image analysis was focused on the origin of the arteries. Any cutoff in signal intensity in the first centimeter of the renal artery was considered to represent significant stenosis. Intraarterial digital subtraction angiography showed 105 renal arteries, including 15 supernumerary renal arteries. Eleven stenoses were localized to the main hilar renal arteries. Using time-of-flight MR angiography, we found that polar supernumerary renal arteries of small caliber and intrarenal branches of renal arteries were not adequately displayed. Using phase-contrast MR angiography to evaluate only whether the main hilar renal arteries were stenotic, we calculated the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy to be 100%, 65%, 28%, 100%, and 69%, respectively. Using a combination of the two imaging sequences, we found that the specificity, positive predictive value, and accuracy were increased to 90%, 58%, and 92%, respectively. For detecting stenoses of the main renal arteries but not for visualizing small accessory renal arteries or distal branches, our results support the use of a combination of the two MR angiography sequences. For now, this combination of sequences should be viewed primarily as a technique for screening patients.

Comparative effects of prolactin, perphenazine and reserpine on non-arteriosclerotic (virgin) vs arteriosclerotic (breeder) rats

Non-arteriosclerotic, virgin and arteriosclerotic breeder rats were subjected to chronic treatment with prolactin or prolactin-releasing drugs such as perphenazine and reserpine for 12 weeks. Males and females responded to the prolactin as evidenced by increased milk secretion, adrenal hyperplasia and thymus gland involution. Although the prolactin- and reserpine-treated animals gained weight and manifested pituitary gland basophilia, the perphenazine-treated animals showed considerable loss of body weight as well as involution of the pituitary gland, ovaries and testes, suggesting a condition of induced hypopituitarism. Chronic treatment with prolactin, both directly and indirectly, caused uniform increases in serum enzymes, e.g., CPK, SGOT, SGPT and LDH, lipids, e.g., triglycerides, free fatty acids and cholesterol, glucose and BUN. Corticosterone production was enhanced by prolactin, reduced by perphenazine and unaffected by reserpine. Prolactin did not induce any arterial disease in the arteriosclerosis-resistant, virgin rats but it did cause exacerbation of the usual severity of arteriosclerosis in the hilar renal arteries of the arteriosclerosis-prone, breeder rats as well as an increased incidence of “old” and “new” foci of myocardial necrosis, characteristically found in breeder rats. It is suggested that hypothalamic control of prolactin as well as ACTH release may play a role in the spontaneous arteriosclerosis which develops in repeatedly-bred, male and female rats.

Fibromuscular dysplasia as a cause of renovascular hypertension.

The renal arteries of five patients with hypertension accompanied by radiologically demonstrable stenosis of the renal arteries were submitted to histological and histometrical examinations. Cases of arteriosclerotic stenosis of the renal artery were not included in the present study. Fibromuscular dysplasias were found in both hilar renal arteries and intrarenal ones, the latter of which caused poststenotic oligemia and provoked hypertension. Subadventitial fibroplasia was attributed to subadventitial hematoma due to medial weakness. Vascular fibroplasia was occasionally found in renal arterioles. In clinically confirmed ischemic area of the kidney there was no hypertensive arterial changes. The arterial muscular coat was found attenuated in such an area.