Efficacy and morbidity of therapeutic renal embolization in the spectrum of urologic disease

Renal arterial embolization: Indications, angiographic findings, and outcomes in a series of 170 patients

Background

The lack of overall experience and reporting on angiographic findings in previously published studies of renal arterial embolization (RAE) compelled us to report our overall experience on a series of patients.

Materials and methods

A retrospective study was performed analyzing data of patients enrolled for RAE between 2010 and 2019. History, physical examination, and laboratory data were reviewed for all patients. Abdominal ultrasound was the initial imaging study, and all patients underwent subsequent computed tomography or magnetic resonance imaging. The outcome of RAE was determined based on radiographic and clinical findings.

Results

Data from 202 patients were analyzed, with a mean age of 45 ± 15 years, and 71.3% of patients were male. Iatrogenic injury was the most common indication for RAE (54%), followed by renal tumors, trauma, and spontaneous, in 27.7%, 10.4%, and 8.4% of patients, respectively. Renal angiography revealing pseudoaneurysm alone or with other pathology in the lower pole of the kidney was the most common finding (40.6%), whereas no lesions were identified on angiography in 32 patients (15.8%), after which RAE was subsequently aborted. Renal arterial embolization was successful in 158 of 170 patients (92.9%) after 1 or more trials (maximum of 4). Microcoil alone or with other embolic materials was the most commonly used material for embolization (85%).

Conclusions

Iatrogenic injury was the most common indication for RAE. Pseudoaneurysm alone or with other lesions was the most common lesion on renal angiography; however, angiography showed a negative result in 16% of patients, even those with symptoms. When lesions are present on angiography, the overall success of repeated trials of RAE reached 92.9%.

Long-term renal function outcomes after renal cryoablation complicated by major hemorrhage requiring selective transarterial embolization

PURPOSE

To determine long-term renal function outcomes after renal cryoablation complicated by major hemorrhage requiring transarterial embolization compared to patients who underwent uncomplicated renal cryoablation without major hemorrhage.

METHODS

Utilizing a matched cohort study design, retrospective review identified 23 patients who underwent percutaneous image-guided renal cryoablation complicated by major hemorrhage requiring ipsilateral transarterial embolization (TAE group) and a control group of 23 patients who underwent uncomplicated renal cryoablation matched 1:1 by age, gender and RENAL Nephrometry score at a single institution from 1/1/2005 to 12/31/2019. Primary outcome parameters included change in creatinine (mg/dl) and estimated glomerular filtration rate (ml/min/1.73 m²; eGFR) from baseline and were compared between TAE and control group using a paired t-test.

RESULTS

There was a significantly higher proportion of patients on pre-ablation anticoagulation in the TAE v. control group (30% v. 4%; p = 0.047), but all patients were off anticoagulation and with normal coagulation parameters at the time of cryoablation. Otherwise there were no significant differences in clinical, renal tumor, Charlson co-morbidity index, baseline renal function or cryoablation parameters between the TAE and control group. In the post-ablation period, there was trend toward greater increase in creatinine from baseline to worst post-ablation creatinine in the TAE v. the control group (+ 0.5 ± 0.7 mg/dl v. 0.2 ± 0.1 mg/dl; p = 0.056). However, at a mean follow-up of 42.7 ± 35.7 months, there was no significant difference between the TAE and control group in creatinine (p = 0.68), eGFR (p = 0.60) or change from baseline in creatinine (p = 0.28), eGFR (p = 0.80) or CKD stage (p = 0.74). No patient required initiation of hemodialysis.

CONCLUSION

Selective transarterial embolization for post-renal cryoablation hemorrhage does not significantly affect long-term renal function compared to cryoablation alone. Pre-ablation anticoagulation despite normal coagulation at time of ablation may be a risk factor for post-ablation hemorrhage, and warrants further evaluation when considering pre-ablation embolization.

Value of Angioembolization in the Treatment of Iatrogenic Renal Vascular Injury Assisted by 3-Dimensional Digital Subtraction Angiography

BACKGROUND This study was conducted to investigate the reliability and efficacy of polyvinyl alcohol combined with coils in the embolization of iatrogenic renal vascular injury with the assistance of 3-dimensional digital subtraction angiography (3D-DSA). MATERIAL AND METHODS Twenty-six patients with minimally invasive renal bleeding who underwent transarterial embolization from January 2012 to January 2019 in our hospital were included in the study. We obtained demographic data from these patients, as well as information on clinical presentation, renal procedures used for treatment, and perioperative details. The changes in renal function tests, serum hemoglobin, serum hematocrit, and technetium Tc 99m dimercaptosuccinic acid (99mTc-DMSA) levels pre- and postembolization were compared. In addition, the embolic area and the technical and clinical success rates were analyzed. Finally, an angiographic manifestation of the renal artery, 3D-DSA, and the effect of embolization were analyzed retrospectively. RESULTS All patients achieved technical and clinical success after embolization (100%, 26/26). There were no significant differences between pre- and postoperative estimated glomerular filtration rate, serum parameters, and 99mTc-DMSA. The embolic area was 12%±10%. Patients did not exhibit severe complications during the follow-up period. CONCLUSIONS Proximal embolization technique assisted by 3D-DSA for renal iatrogenic hemorrhage and vascular lesions is both safe and efficacious, offering high rates for both clinical and technical success. It maximizes the protection of the kidney and reduces the rate of renal resection.

Renal Artery Embolization for Acute Renal Hemorrhage: A Single-Center Experience

Background

Emergency renal artery embolization (RAE) is a useful method in treating renal trauma and bleeding renal tumors. The aim of this study was to evaluate the clinical efficacy and safety of emergency RAE, and factors associated with RAE failure.

Methods

This retrospective study included patients treated with emergency RAE for acute renal hemorrhage between 1 January 2009 and 31 October 2019 in Srinagarind Hospital. The embolization was performed using coils, glues, and/or gel foams. Factors associated with unsuccessful outcomes were analyzed using univariate and multivariate regression analyses.

Results

A total of 94 patients were treated at the center during the study period with the clinical success rate of 91.5%. The most common cause of acute renal hemorrhage was iatrogenic injury (76.5%). Factors associated with unsuccessful RAE according to multivariate analyses were hypertension (adjusted odds ratio [AOR] 24.2) and ruptured tumor/aneurysm (AOR 26.8).

Conclusion

RAE is an effective procedure for acute renal hemorrhage. Hypertension and ruptured tumor/aneurysm were negative predictors for success.

Use of angioembolization in urology: a review

This review discusses current and developing indications for angioembolization (AE) techniques in urology cases, including trauma and non-trauma uses for kidney, prostate, and bladder conditions. AE methods, complications and technical and clinical outcomes are outlined for each indication for the purpose of aiding urologists in selecting ideal candidates for this procedure.

Image-guided urological interventions: What the urologists must know

Advances in imaging technology, especially in the last two decades, have led to a paradigm shift in the field of image-guided interventions in urology. While the traditional biopsy and drainage techniques are firmly established, image-based stone management and endovascular management of hematuria have evolved further. Ablative techniques for renal and prostate cancer and prostate artery embolization for benign prostatic hypertrophy have evolved into viable alternative treatments. Many urologic diseases that were earlier treated surgically are now effectively managed using minimally invasive image-guided techniques, often on a day care basis using only local anesthesia or conscious sedation. This article presents an overview of the technique and status of various image-guided urological procedures, including recent emerging techniques.

Renal artery embolization-indications, technical approaches and outcomes

Owing to improvements in catheters and embolic agents, renal artery embolization (RAE) is increasingly used to treat nephrological and urological disease. RAE has become a useful adjunct to medical resuscitation in severe penetrating, iatrogenic or blunt renal traumatisms with active bleeding, and might avoid surgical intervention, particularly among patients that are haemodynamically stable. The role of RAE in pre-operative or palliative management of advanced malignant renal tumours remains debated; however, RAE is recommended as a first-line therapy for bleeding angiomyolipomas and can be used as a preventative treatment for angiomyolipomas at risk of bleeding. RAE represents an alternative to nephrectomy in various medical conditions, including severe uncontrolled hypertension among patients with end-stage renal disease, renal graft intolerance syndrome or autosomal dominant polycystic kidney disease. RAE is increasingly used to treat renal artery aneurysms or symptomatic renal arteriovenous malformations, with a low complication rate as compared with surgical alternatives. This Review highlights the potential use of RAE as an adjunct in the management of renal disease. We first compare and contrast the technical approaches of RAE associated with the various available embolization agents and then discuss the complications associated with RAE and alternative procedures.

Treatment of angiomyolipoma at a tertiary care centre: the decision between surgery and angioembolization

BACKGROUND

Angiomyolipoma (AML) is a benign renal neoplasm. First-line therapy includes renal preserving surgery or angioembolization (RAE), both with good outcomes in isolated studies. However, there are no comparative randomized trials and no clinical guidelines to help clinicians decide between these treatment modalities. Our study examines the patterns of AML treatment at a tertiary care centre to evaluate how local urologists have been treating this disease.

METHODS

This is a retrospective study of all AMLs treated at the Vancouver General Hospital (Vancouver, BC, Canada) over the past 10 years with either RAE or surgical excision. Searches were performed of the radiology and pathology dictation systems, using the following keywords: AML, angiomyolipoma, angioembolization, embolization, surgery, partial nephrectomy and nephrectomy.

RESULTS

At our institution, more AMLs were treated by surgery than angioembolization (42 vs. 17 cases). Angioembolization was more often chosen for cases of multifocal AML (35% vs. 7%) and acute hemorrhage (50% vs. 14%). In the angioembolization cases, particles were the embolic agent of choice (used 40% of the time).

CONCLUSIONS

Angioembolization allows rapid patient stabilization in cases of acute hemorrhage, and provides good renal preservation in cases of multifocal AML. It may also be preferred in large masses when partial nephrectomy is not feasible. Surgery should be performed in cases of diagnostic uncertainty or complex vascular anatomy not amenable to RAE. Prospective randomized studies are needed to compare RAE and surgery to better define their indications in sporadic AML.

Interventional uroradiology

With advances in imaging capabilities and percutaneous instruments, many urologic diseases that were once managed surgically are now managed with minimally invasive image-guided techniques. Interventional uroradiology has evolved from simple renal biopsies for diagnostic confirmation, to percutaneous management of stones, to ablation of renal and adrenal tumors. Central to this evolution is the close cooperation with the urologist and nephrologist, each of whom provides specific skill sets and knowledge that can be used to successfully manage the patient. The purpose of this article is to detail the wide range of image-guided interventional techniques, including a discussion of indications, methods, success rates, and complications.

Embolização pré operatória de tumores renais com microparticulas esféricas de tecnologia nacional. (Spherus®-First line Brasil)

Os autores relatam pela primeira vez utilização de uma nova partícula para embolização, constituída de um núcleo de acetato de polivinil revestido por polivinil-álcool, de forma esférica (Spherus®-First Line Brasil), como preparo pré-operatório em três pacientes portadores de neoplasia renal, na intenção de diminuir o tamanho do tumor e prevenir complicações hemorrágicas durante o ato operatório. Estas novas partículas foram projetadas e elaboradas nos laboratórios da COPPE/UFRJ. A embolização intra-arterial pré-operatória com estas novas partículas ocasionou acentuada isquemia em todo o tecido tumoral facilitando o procedimento cirúrgico.