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Purpose To determine demographics, practice patterns, needs from Society of Interventional Radiology (SIR), and preferences of interventional radiologists (IRs) early in their careers. Methods A 28-question descriptive survey was used to identify demographic and practice composition, practice issues, and needs of early career IRs. The survey was distributed to SIR members in the United States (US) (n = 859) within the first 8 years of practice, with 213 respondents (25%). Results Respondents were primarily male (n = 181, 87%), less than 40 years old (n = 156, 73%), in practice for 6 years or less (n = 167, 79%), and satisfied with IR as a career (n = 183, 92.4%). The majority were in academic practice (n = 89, 43.2%) or large private practice group (n = 67, 32.5%). Most respondents read diagnostic imaging daily or weekly (n = 130, 61%). The majority of respondents perform complex procedures regularly including transarterial tumor therapy, percutaneous tumor ablation, peripheral arterial interventions, and biliary interventions monthly. Many respondents (n = 49, 23%) have changed jobs at least once citing career advancement, practice issues/disagreements, or compensation as reason. Most respondents would serve as mentors (n = 170, 80%) for trainees and were satisfied with their career mentorship (n = 166, 78%). Respondents felt that mentorship, identification of barriers facing early career IRs, and networking should be the most important functions of the Early Career Section (ECS)of the SIR. Conclusion As nearly all survey respondents indicated that early career IRs have different needs and priorities than established physicians, they felt that mentorship, identification of barriers facing early career IRs, and networking should be the most important functions of the ECS. Additionally, this same group of IRs report low comfort with the business side of medicine and may benefit from directed content provided by the SIR ECS.

Female physicians in academic medicine have faced barriers that potentially affect representation in different fields and delay promotion. Little is known about gender representation differences in United States academic radiology departments, particularly within the most pursued subspecialties.To determine whether gender differences exist in United States academic radiology departments across seven subspecialties with respect to academic ranks, departmental leadership positions, experience, and scholarly metrics.In this cross-sectional study from November 2018 to June 2020, a database of United States academic radiologists at 129 academic departments in seven subspecialties was created. Each radiologist's academic rank, departmental leadership position (executive-level - Chair, Director, Chief, and Department or Division Head vs vice-level - vice, assistant, or associate positions of executive level), self-identified gender, years in practice, and measures of scholarly productivity (number of publications, citations, and h-index) were compiled from institutional websites, Doximity, LinkedIn, Scopus, and official NPI profiles. The primary outcome, gender composition differences in these cohorts, was analyzed using ChiOverall, 5086 academic radiologists (34.7% women) with a median 14 years of practice (YOP) were identified and indexed. There were 919 full professors (26.1% women, p0.01) and 1055 executive-level leadership faculty (30.6% women, p0.01). Within all subspecialties except breast imaging, women were in the minority (35.4% abdominal, 79.1% breast, 12.1% interventional, 27.5% musculoskeletal, 22.8% neuroradiology, 45.1% pediatric, and 19.5% nuclear; p0.01). Relative to subspecialty gender composition, women full professors were underrepresented in abdominal, pediatric, and nuclear radiology (p0.05) and women in any executive-level leadership were underrepresented in abdominal and nuclear radiology (p0.05). However, after adjusting for h-index and YOP, gender did not influence rates of professorship or executive leadership. The strongest single predictors for professorship or executive leadership were h-index and YOP.Women academic radiologists in the United States are underrepresented among senior faculty members despite having similar levels of experience as men. Gender disparities regarding the expected number of women senior faculty members relative to individual subspecialty gender composition were more pronounced in abdominal and nuclear radiology, and less pronounced in breast and neuroradiology. Overall, h-index and YOP were the strongest predictors for full-professorship and executive leadership among faculty.● Though women comprise 34.7% of all academic radiologists, women are underrepresented among senior faculty members (26.1% of full professors and 30.6% of executive leadership) ● Women in junior faculty positions had higher median years of practice than their male counterparts (10 vs 8 for assistant professors, 21 vs 13 for vice leadership) ● Years of practice and h-index were the strongest predictors for full professorship and executive leadership.

Lymphatics have long been overshadowed by the remainder of the circulatory system. Historically, lymphatics were difficult to study because of their small and indistinct vessels, colorless fluid contents, and limited effective interventions. However, the past several decades have brought increased funding, advanced imaging technologies, and novel interventional techniques to the field. Understanding the history of lymphatic anatomy and physiology is vital to further realize the role lymphatics play in most major disease pathologies and innovate interventional solutions for them.

Interventional Radiology (IR) was officially approved by the American Board of Medical Specialties in 2012 and the Accreditation Council of Graduate Medical Education as a unique, integrated residency in 2014. Its establishment and distinction from diagnostic radiology was compelled by the increasing emphasis on clinical care delivery by IRs. The shift in the IR training paradigm, as exemplified in the Integrated IR residency programs, appeals to a distinct cohort of applicants, prompting the need to re-evaluate the recruitment and selection process. This article discusses selection criteria for identifying ideal candidates for the new IR training model (focusing on Integrated IR residency training), highlights the importance of collaboration between the IR and DR selection committees, and illustrates the changes made at a single institution over the course of 4 selection cycles prior to the COVID-19 pandemic as well as significant changes in the current climate of the global pandemic.

Traumatic chylothorax occurs more often now than in historic reports. In part, this is due to the increased ability to perform more advanced and aggressive thoracic resections and cardiovascular surgeries as well as the improved mortality of cancer patients. If untreated, chylothorax can result in significant morbidity and mortality, particularly in patients with underlying malignancy. Thoracic duct embolization for chylothorax was the first successful lymphatic intervention and has been performed for over 20 years. An overview of the clinical and technical approach to thoracic duct embolization for traumatic chylothorax is presented in addition to a review of outcomes.

Purpose To assess the 2-year effectiveness and safety of balloon-occluded retrograde transvenous obliteration (BRTO) for gastric varices (GVs) in liver transplant recipients. Materials and methods Eleven liver transplant recipients underwent consecutive BRTO for GVs at four institutions. Patients included eight (73%) men and three (27%) women with mean age of 56 years ± 12 (SD) (range: 26–67 years). Underlying cause of liver transplantation was hepatitis C virus (HCV)-related cirrhosis in five (45%), alcohol- and HCV-related cirrhosis in three (27%), primary biliary cirrhosis in two (18%), and alcoholic cirrhosis in one (9%). Five (45%) patients underwent BRTO for actively bleeding GVs, three (17%) for high-risk GVs, and three (17%) for augmentation of portal venous flow through obliteration of gastrorenal shunts. Mean time between liver transplantation and BRTO was 78 months (range: 0.1–276 months). Technical success, GVs obliterative rates, and immediate complications were recorded. Post-BRTO hemorrhagic, transplant, and overall survival rates were evaluated at 6, 12, and 24 months. Results All (100%) procedures were technically successful. Complete GVs obliteration was achieved in ten patients (91%). Two major complications (18%) occurred in the immediate post-procedure period. One patient developed complete portal vein thrombosis, and another patient developed consumptive coagulopathy, ultimately leading to death. No post-BRTO hemorrhagic recurrences were seen at 6, 12, or 24 months. One patient (9%) had delayed upper gastrointestinal bleeding at 34 months after the procedure which was managed conservatively. Transplant and overall survival rates were 91% at 6, 12, and 24 months. Conclusion BRTO has high technical success and complete GVs obliterative rates in liver transplant recipients with few complications and high graft survival rates.

Percutaneous image-guided ablation is performed throughout many areas of the body for various pathologies including hepatic malignancies. Heat and cold-based ablative technologies are effective and well-tolerated with an acceptable safety profile. However, ablative therapies may be technically more challenging and cause collateral thermal injury if the targeted lesion is adjacent to critical organs. Previously, techniques including artificial ascites and pneumoperitoneum have been utilized to displace or insulate critical structures from the ablation zone. This technical innovation describes (10-30 mL) fibrillar collagen dissolved in fluid as a focal thermal insulation technique. Small volume fibrillar collagen instillation, and thermal ablation were technically successful in three cases without complication. Clinical follow-up and 3-month imaging confirmed complete ablation of all hepatic malignancies without collateral injury.

Percutaneous image-guided biopsies of pancreatic malignancies may prove challenging and nondiagnostic due to a variety of anatomic considerations. For patients with complex post-surgical anatomy, such as a Roux-en-Y gastric bypass, diagnosis via endoscopic ultrasound with fine-needle aspiration may not be possible because of an inability to reach the proximal duodenum. This report describes the first diagnostic case of transbiliary intravascular ultrasound-guided biopsy of a pancreatic head mass in a patient with prior Roux-en-Y gastric bypass for which a diagnosis could not be achieved via percutaneous and endoscopic approaches. Transbiliary intravascular ultrasound-guided biopsy resulted in a diagnosis of pancreatic adenocarcinoma, allowing the initiation of chemotherapy.

Aortoenteric fistulae are life-threatening conditions characterized by abnormal communications between the aorta and gastrointestinal tract. Aortoenteric fistulae may be characterized by the triad of bleeding, abdominal pain, or a pulsatile abdominal mass. Although hemorrhage is the most common presentation, it does not always occur; thus, patients may present with nonspecific symptoms. Computed tomography angiography findings suggestive of aortoenteric fistulae include ectopic gas within or adjacent to the aorta, discontinuity of the aortic wall, bowel wall thickening, and extravasation of contrast into the bowel. Endovascular treatments include retrograde balloon occlusion of the aorta and stent-graft deployment as well as coil, fibrin, and glue embolization of the fistulous tract. This report describes 3 cases of aortoenteric fistulae temporized and treated by interventional radiology and vascular and cardiac surgery at a single institution in an effort to increase awareness of this important clinical condition.

N-butyl cyanoacrylate glue is well established as a transcatheter or direct injection embolic agent. Herein, targeted glue embolization was performed by direct needle injection into peripheral portal branches and along the surface of the liver to directly treat actively extravasating portal venous injury. In both cases, hemodynamically unstable patients underwent exploratory laparotomy, which was not able to definitively treat the hemorrhage. Subsequently, emergent visceral angiography and indirect portography revealed active portal phase extravasation. Transhepatic direct needle injection of the peripheral portal active extravasation with glue was successful in both cases and the patients stabilized, demonstrating this as an efficacious salvage approach.

OBJECTIVE: To develop and assess the accuracy of an augmented reality (AR) needle guidance smartphone application. METHODS: A needle guidance AR smartphone application was developed using Unity and Vuforia SDK platforms, enabling real-time displays of planned and actual needle trajectories. To assess the application’s accuracy in a phantom, eleven operators (including interventional radiologists, non-interventional radiology physicians, and non-physicians) performed single-pass needle insertions using AR guidance (n = 8) and CT-guided freehand (n = 8). Placement errors were measured on post-placement CT scans. Two interventional radiologists then used AR guidance (n = 3) and CT-guided freehand (n = 3) to navigate needles to within 5 mm of targets with intermediate CT scans permitted to mimic clinical use. The total time and number of intermediate CT scans required for successful navigation were recorded. RESULTS: In the first experiment, the average operator insertion error for AR-guided needles was 78% less than that for CT-guided freehand (2.69 ± 2.61 mm vs. 12.51 ± 8.39 mm, respectively, p < 0.001). In the task-based experiment, interventional radiologists achieved successful needle insertions on each first attempt when using AR guidance, thereby eliminating the need for intraoperative CT scans. This contrasted with 2 ± 0.9 intermediate CT scans when using CT-guided freehand. Additionally, average procedural times were reduced from 13.1 ± 6.6 min with CT-guided freehand to 4.5 ± 1.3 min with AR guidance, reflecting a 66% reduction. CONCLUSIONS: All operators exhibited superior needle insertion accuracy when using the smartphone-based AR guidance application compared to CT-guided freehand. This AR platform can potentially facilitate percutaneous biopsies and ablations by improving needle insertion accuracy, expediting procedural times, and reducing radiation exposures.

Management of bleeding gastric varices (GV) presents a unique challenge for patients with portal hypertension. Despite over thirty years of diagnostic and treatment advances standardized practices for bleeding GV are lacking and unsupported by adequate evidence. There are no definitive natural history studies to help with risk assessment or prospective clinical trials to guide clinical decision making. Available literature on the natural history and management of gastric varices consists of case series, restricted cohort studies, and a few small randomized trials, all of which have significant selection biases. This review summarizes the available data and recommendations based on expert opinion on how best to diagnose and manage bleeding from gastric varices. Table 1 summarizes our recommendations.

The training paradigm of the interventional radiologist has quickly evolved with the approval of the integrated interventional radiology (IR) residency by the American Board of Medical Specialties and the Accreditation Council of Graduate Medical Education. Prior to appointment in an integrated IR program, a resident must complete a preliminary clinical year, which may be surgical, medical, or transitional. The unique procedural- and clinical-based skillset required of the IR resident is best aligned with a surgical preliminary year. The following is a review of the steps to successful creation of a surgical preliminary year based on a single institution's experience.

The term "portosystemic shunt syndrome" was coined by Kumamoto et al referring to reduction of the hepatic reserve (reflected by progression of the Child-Pugh score) over 5 years compared with portal hypertensive cirrhotics without gastrorenal shunts or with prior history of obliterated gastrorenal shunts. Saad et al elaborated on this term further by describing a complete syndrome with clinical findings (including worsening liver failure and hepatic encephalopathy [HE]) and imaging findings (including hepatic atrophy, portal vein thrombosis, and paucity of intrahepatic portal vein radicles). This article discusses the syndrome in detail. In addition, the article describes the types of HE and the endovascular management of shunt-related HE.

Purpose: The purpose of this study is to quantify hepatic arterial flow (HAF) in liver transplants with splenic steal syndrome (SSS) pre- and post-test balloon occlusion of the splenic artery utilizing Doppler ultrasound (DUS) and quantitative digitally subtracted angiography (Q-DSA). Methods: A total of 193 liver transplants were evaluated retrospectively. Hepatic arterial velocity (HAV) and HAF were calculated utilizing DUS and Q-DSA (i-flow prototype, Siemens) pre- and post-splenic artery balloon occlusion. The rate of HAF increase, total HAF, and peak contrast density (PKD) by Q-DSA were compared with HAF by DUS. Results: Of all, 4 suspected SSS cases underwent test-balloon occlusion with DUS and Q-DSA. Using DUS, HAV and HAF increased by 1.6- to 1.8-fold and 1.7- to 2.6-fold, respectively. Using Q-DSA, the HAF rate, total HAF, and PKD increased by 1.1 to 12.8, 1.5 to 7.6, and 1.3 to 5.3, respectively. Conclusion: Occlusion of the splenic artery in liver transplants with SSS doubles the HAF (+1.7- to 2.6-fold). The Q-DSA parameters correlate qualitatively but overestimate the resultant increased HAF.

Patients with gastric variceal bleeding require a multidisciplinary team approach including hepatologists, endoscopists, diagnostic radiologists, and interventional radiologists. Upper gastrointestinal endoscopy is the first-line diagnostic and management tool for bleeding gastric varices, as it is in all upper gastrointestinal bleeding scenarios. In the United States when endoscopy fails to control gastric variceal bleeding, a transjugular intrahepatic portosystemic shunt (TIPS) traditionally is performed along the classic teachings of decompressing the portal circulation. However, TIPS has not shown the same effectiveness in controlling gastric variceal bleeding that it has with esophageal variceal bleeding. For the past 2 decades, the balloon-occluded retrograde transvenous obliteration (BRTO) procedure has become common practice in Asia for the management of gastric varices. BRTO is gaining popularity in the United States. It has been shown to be effective in controlling gastric variceal bleeding with low rebleed rates. BRTO has many advantages over TIPS in that it is less invasive and can be performed on patients with poor hepatic reserve and those with encephalopathy (and may even improve both). However, its by-product is occlusion of a spontaneous hepatofugal (TIPS equivalent) shunt, and thus it is contradictory to the traditional American doctrine of portal decompression. Indeed, BRTO causes an increase in portal hypertension, with potential aggravation of esophageal varices and ascites. This article discusses the concept, technique, and outcomes of BRTO within the broader management of gastric varices.

Percutaneous portal vein interventions require minimally invasive access to the portal venous system. Common approaches to the portal vein include transjugular hepatic vein to portal vein access and direct transhepatic portal vein access. A major concern of the transhepatic route is the risk of postprocedural bleeding, which is increased when patients are anticoagulated or receiving pharmaceutical thrombolytic therapy. Thus percutaneous portal vein access and subsequent closure are important technical parts of percutaneous portal vein procedures. At present, various techniques have been used for either portal access or subsequent transhepatic tract closure and hemostasis. Regardless of the method used, meticulous technique is required to achieve the overall safety and effectiveness of portal venous procedures. This article reviews the various techniques of percutaneous transhepatic portal vein access and the various closure and hemostatic methods used to reduce the risk of postprocedural bleeding.

To describe the management and treatment of iatrogenic pseudoaneurysms (PSAs) by interventional radiology (IR) at a single institution. 50 patients with iatrogenic PSAs were identified from 2014 until 2016. Patients included 31 (62%) males and 19 (38%) females with mean age of 65 years (range: 34

The gastric varices communicate with gastrorenal and gastrocaval shunts and are classified according to the pattern of venous inflow into three types, which differ in the number and location of the inflow veins. The gastric varices are also classified according to their venous drainage into four different types, reflecting the size and number of collateral veins communicating with the gastric varices and the gastrorenal/gastrocaval shunt. Lastly, the gastric varices are classified according to their appearance on balloon-occluded retrograde venography into five grades representing the degree of opacification of the gastric varices and the collateral veins. Understanding these anatomic classifications is crucial in planning endovascular obliteration of gastric varices.

The American College of Radiology Appropriateness Criteria Committee on interventional radiology has recently recognized balloon-occluded retrograde transvenous obliteration (BRTO) as a viable alternative to transjugular intrahepatic portosystemic shunt (TIPS) in certain anatomic and clinical scenarios for the management of gastric varices. However, it did not define these particular scenarios where BRTO would be a viable alternative. With the increased practice of BRTO in the United States, a debate ensues in the United States and Europe whether BRTO or TIPS should be the primary endovascular procedure of choice for gastric varices. From a conservative standpoint, BRTO is reserved for patients who are not TIPS candidates, while other institutions leave the decision to operator preference and “favorable anatomy” for either procedure. To add to the debate, there is a heightened interest in the improved efficacy of variceal embolization (metallic/bland embolization) concurrent with TIPS compared with TIPS without embolization, and a recent article describing a combination of TIPS and BRTO that demonstrated impressive results superior to BRTO or TIPS alone. This article discusses the most recent outcomes of TIPS and embolization of gastric varices as well as combining BRTO and TIPS.

[This corrects the article DOI: 10.1055/s-0038-1642043.].

We report our experience treating four patients with acutely bleeding angiomyolipoma (AML) of sizes between 4 and 12 cm who were managed with endovascular embolisation with a mean follow-up of 10 months. In our case series, we demonstrate that endovascular embolisation in the acute setting for bleeding AMLs is a viable treatment option. AML should be in the differential diagnosis of acutely bleeding renal masses, even when there is no fat assessed by computed tomography (CT) imaging in the renal mass.

BackgroundThe intent of endovascular therapy for symptomatic atherosclerotic renal artery stenosis (ARAS) is to preserve parenchyma and avoid renal-related morbidity. The aim of this study is to examine the impact of renal artery intervention on parenchymal preservation.MethodsWe performed a retrospective analysis of records from patients who underwent endovascular intervention for ARAS and were followed by duplex ultrasound between 1990 and 2008. Renal volume (in cm3) was estimated in all patients as renal length (cm) × renal width (cm) × renal depth (cm) × 0.5. The normal renal volume was calculated as 2 × body weight (kg) in cm3. Failure of preservation was considered to be a persistent 10% decrease in volume. Clinical benefit defined as freedom from renal-related morbidity (increase in persistent creatinine >20% of baseline, progression to hemodialysis, death from renal-related causes) was calculated.ResultsFive hundred ninety-two renal artery interventions were performed. One hundred eighty-six kidneys suffered parenchymal loss (>5%) with an actuarial parenchymal loss rate of 29% ± 1% at five years respectively. There were no significant differences in age, gender, starting renal volume, or kidney size. However, patients with parenchymal loss had lower eGFR (45 ± 24 vs 53 ± 24 mL/min/1.73 m2; Loss vs noLoss, P = .0002, Mean ± SD) higher resistive index (0.75 ± 0.9 vs 0.73 ± 0.10; P = .0001) and worse nephrosclerosis grade (1.43 ± 0.55 vs 1.30 ± 0.49; P = .006) then those not suffering parenchymal loss. Parenchymal loss was associated with significantly worse five-year survival (26% ± 4% vs 48% ± 2%; Loss vs noLoss; P < .001) and freedom from renal-related morbidity (70% ± 5% vs 82% ± 2%; P < .05) with increased numbers progressing to dialysis (17% vs 7%; P < .006).ConclusionWhile parenchymal preservation occurs in most patients, parenchymal loss occurs in 31% of patients and is associated with markers of impaired parenchymal perfusion (resistive index and nephrosclerosis grade) at the time of intervention. Pre-existing renal size or volumes were not predictive of parenchymal loss. Parenchymal loss is associated with a significant decrease in survival and a marked increased renal related morbidity and progression to hemodialysis.

BackgroundEndovascular therapy for symptomatic atherosclerotic renal artery stenosis (ARAS) is common and effective in the well-selected patient. Hypertension is a common indication for intervention and a major component of metabolic syndrome (MetS). The impact of MetS on outcomes after percutaneous renal intervention is unknown.MethodsWe performed a retrospective analysis of records from patients who underwent endovascular intervention for ARAS and were followed by duplex ultrasound between January 1990 and January 2008. MetS was defined as the presence of ≥3 of the following criteria: Blood pressure ≥140 mm Hg/≥90 mm Hg; triglycerides ≥150 mg/dL; high-density lipoprotein ≤50 mg/dL for women and ≤40 mg/dL for men; fasting blood glucose ≥110 mg/dL; or body mass index ≥30 kg/m2. The average follow-up period was 3.3 years. Clinical benefit defined as freedom from renal-related morbidity (increase in persistent creatinine >20% of baseline, progression to hemodialysis, death from renal-related causes) or freedom from recurrent hypertension, anatomic patency, restenosis, and patient survival were measured.ResultsFive hundred ninety-two renal artery interventions were performed in 427 patients. Fifty-two percent were identified as having MetS. Patients with MetS were more often female (35% vs 50%, NoMetS vs MetS). There were no significant differences in presenting symptoms. There was no peri-operative mortality and equivalent morbidity (6% vs 7%, NoMetS vs MetS). Patients with MetS had equivalent survival and cumulative patency. However, the MetS group had a lower five-year freedom from restenosis (87±2% vs 69±9%, NoMetS vs MetS; P < .01) and lower five-year retained clinical benefit (71±8% vs 45±8%, NoMetS vs MetS; P < .01) with a higher number progressing to hemodialysis (3% vs 13%, NoMetS vs MetS; P < .01). Individually, the components of MetS did not influence outcomes. Statin therapy did not influence outcomes.ConclusionMetS is associated with markedly reduced renal clinical benefit and increased progression to hemodialysis following endovascular intervention for atherosclerotic renal artery stenosis. MetS is thus a risk factor for poor long-term outcomes following renal interventions.

BackgroundEndovascular therapy for symptomatic atherosclerotic renal artery stenosis (ARAS) is common but is associated with a significant restenosis rate. This study evaluates the outcomes of percutaneous endoluminal therapy for symptomatic restenosis (>50% on angiography) after renal intervention.MethodsWe performed a retrospective analysis of records from patients who underwent endovascular intervention for ARAS and were followed by duplex ultrasound scan between January 1990 and January 2008. Clinical benefit defined as freedom from recurrent hypertension or renal-related morbidity (increase in persistent creatinine >20% of baseline, progression to hemodialysis, death from renal-related causes), anatomic patency, restenosis, and patient survival were measured.ResultsA total of 447 patients underwent 619 renal artery interventions. A total of 80 vessels restenosed with an actuarial restenosis rate of 19% at 5 years. Of these restenoses, 65 (81%) were associated with recurrent symptoms (recurrent hypertension 84%, or continuing deterioration in renal function 16%). Fifty-five (85%) underwent repeat angioplasty and 10 underwent bypass surgery. The remainder was observed. The 55 percutaneous interventions were performed in 51 patients (61% female, average age 62 years, range, 51-85). A total of 73% had metabolic syndrome, 58% had hyperlipidemia, and 51% were considered diabetic; all of them had primary stenting during their first procedure. There was a 4% technical failure rate in both groups. In the restenosis group, the presence of stent was associated with a 9% technical failure rate, while in the absence of a stent the technical failure rate was only 3% (P < .05). At 5 years, outcomes were equivalent between the primary and recurrent groups for survival (76 ± 2% vs 75 ± 8%, primary vs recurrent), cumulative patency (82 ± 3% vs 70 ± 10%), freedom from restenosis (81 ± 3% vs 81 ± 9%), and retained clinical benefit (44 ± 4% vs 46 ± 10%). By Cox proportional hazards and multivariate analysis, administration of statins were associated with freedom from restenosis in the recurrent lesions. Statins, contralateral kidney size (>9 cm) and a ≥20% improvement in baseline creatinine with 3 months were associated with freedom from recurrent symptoms. Restenosis after therapy in recurrent lesions was significantly correlated with recurrent symptoms (Spearman r = 0.4614, P < .0004).ConclusionPercutaneous reintervention for renal artery restenosis is safe and effective with equivalent outcomes to primary intervention. The patients are more likely to present with recurrent hypertension and be younger and of female gender than patients presenting for primary intervention. Functional outcomes after reintervention are equivalent to primary intervention.

Sonoelastography has been developed as an ultrasound-based elasticity imaging technique. In this technique, external vibration is induced into the target tissue. In general, tissue stiffness is inversely proportional to the amplitude of tissue vibration. Imaging tissue vibration will provide the elasticity distribution in the target region. This study investigated the feasibility of using real-time sonoelastography to detect and estimate the volume of thermal lesions in porcine livers in vivo. A total of 32 thermal lesions with volumes ranging from 0.2 to 5.3 cm3 were created using radiofrequency ablation (RFA) or high-intensity focused ultrasound (HIFU) technique. Lesions were imaged using sonoelastography and coregistered B-mode ultrasound. Volumes were reconstructed from a sequence of two-dimensional scans. The comparison of sonoelastographic measurements and pathology findings showed good correlation with respect to the area of the lesions (r2=0.8823 for RFA lesions, r2=0.9543 for HIFU lesions). In addition, good correspondence was found between three-dimensional sonoelastography and gross pathology (3.6% underestimate), demonstrating the feasibility of sonoelastography for volume estimation of thermal lesions. These results support that sonoelastography outperforms conventional B-mode ultrasound and could potentially be used for assessment of thermal therapies.

Introduction Central (superior vena cava, brachiocephalic, or subclavian) venous stenoses are a major impediment to long-term arteriovenous access in the upper extremities. The optimal management of these stenoses is still undecided. The purpose of this study was to determine the outcomes of primary angioplasty (PTA) vs primary stenting (PTS) in a dialysis access population at a tertiary referral academic medical center. Methods A database of consecutive hemodialysis patients undergoing endovascular treatment for central venous stenosis was developed for the period 1995 through 2003. This database was retrospectively reviewed. Vessels exposed to either primary high-pressure balloon angioplasty or primary stenting were examined. Vessels undergoing stenting after failed or suboptimal angioplasty were defined as failures at the time of stenting despite the potential continued patency upon completion of stenting. Kaplan-Meier survival analyses were performed to assess time-dependent outcomes. Cox proportional hazards analysis was performed for time-dependent variables. Data are presented as mean ± standard deviation where appropriate. Results PTS was used to treat 26 patients (35% male; average age, 57 ± 15 years) with 26 central venous stenoses, and 47 patients (45% male; average age, 57 ± 18 years) with 49 central venous stenoses were treated with PTA. The PTS group underwent 71 percutaneous interventions per stenosis (average, 2.7 ± 2.4 interventions), and the PTA group underwent 98 interventions per stenosis (average, 2.0 ± 1.6 interventions). The PTS group hemodialysis access site was an average of 1.0 ± 1.3 years old at the time of the initial intervention, and the hemodialysis access in the PTA group was an average of 1.1 ± 1.2 years old. Primary patency was equivalent between groups by Kaplan-Meier analysis, with 30-day rates of 76% for both groups and 12-month rates of 29% for PTA and 21% for PTS ( P = .48). Assisted primary patency was also equivalent ( P = .08), with a 30-day patency rate of 81% and 12-month rate of 73% for the PTA group, vs PTS assisted patency rates of 84% at 30 days, and 46% at 12 months. Ipsilateral hemodialysis access survival was equivalent between groups. Conclusions Endovascular therapy with PTA or PTS for central venous stenosis is safe, with low rates of technical failure. Multiple additional interventions are the rule with both treatments. Although neither offers truly durable outcomes, PTS does not improve on the patency rates more than PTA and does not add to the longevity of ipsilateral hemodialysis access sites.

Balloon-retrograde transvenous obliteration (BRTO) can be an appropriate treatment modality for hepatic encephalopathy in the setting of portal-systemic shunting in selected patients. We describe a case of a large gastro-renal shunt that was successfully treated via combined BRTO and expandable hydrogel-coated coil embolization, with an emphasis on technique.

To describe the radiographic appearance of distressed intravascular implants as a predictor of venous stenosis or occlusion and to determine the success of reparative endovascular procedures. 73 patients with distressed stents or inferior vena cava (IVC) filters characterized by pursing

The transjugular intrahepatic portosystemic shunt (TIPS) has long been referred to as a procedure performed as “a bridge to transplantation” since, like many other portosystemic shunts, it decompresses the portal circulation and stabilizes patients but does not definitively treat portal hypertension. One of the major advantages of TIPS over surgically placed portosystemic shunts in the transplant era is that the TIPS is intrahepatic and is removed in situ with the native liver, and usually does not need additional surgery (unlike takedown/ligation of surgical shunts). There are several studies that evaluate TIPS before transplantation—not as a bridge/temporizing measure, but as a prelude to the transplant to decompress the portal circulation and reduce portosystemic engorgement and collaterals and thus, in theory, reduce intraoperative bleeding during liver transplantation. However, these studies, mostly in the transplant literature, have been equivocal from an intraoperative and posttransplant clinical outcome standpoint. TIPS creation in liver transplant recipients is another interesting aspect of TIPS. There has been a debate about whether or not liver transplantation adds additional technical difficulty to the TIPS procedure. Initially, many theories were proposed as to the technical difficulty of TIPS in a transplanted liver. However, recent opinions and published studies demonstrate that whole-graft liver transplantation does not pose a significant technical difficulty to TIPS. Moreover, there are several recent studies evaluating the outcomes of TIPS in liver transplant recipients, showing that outcomes are less favorable when compared with TIPS in nontransplanted patients. This article discusses the results of TIPS as a preoperative prelude to liver transplantation. In addition, it discusses the technical and clinical outcomes of TIPS in liver transplant recipients.

Objectives: Endoscopic experience in the management of duodenal varices (DVs) is limited and challenging given the anatomic constraints and limited experience. The endovascular management of DVs is not yet established and the controversy of whether to manage them by decompression with a transjugular intrahepatic portosystemic shunt (TIPS) or by transvenous obliteration is unresolved. In the literature, the 6-12 month rebleeding rate of DVs after TIPS is 21-37% and after transvenous obliteration is 13%. The purpose of the study is to evaluate the clinical outcome of combined TIPS decompression and transvenous obliteration/sclerosis. Materials and Methods: This is a retrospective study (case series) of two institutions, evaluating patients who underwent TIPS and/or transvenous obliteration/sclerosis for bleeding DVs (from January 2009 to June 2013). TIPS was performed according to a standard procedure using covered stents. Transvenous obliteration (variceal sclerosis) from the systemic and/or portal venous circulation was performed utilizing 3% sodium tetradecyl sulfate foam. Transvenous obliteration was commonly augmented with coils and/or vascular plugs. Technical (technical success of establishing TIPS and completely obliterating the DVs) and clinical outcomes (rebleeding rate and survival) were evaluated. Results: Five patients with liver cirrhosis presenting with bleeding DVs were included in the study with all eventually (and coincidentally) receiving TIPS and transvenous obliteration. Two of the five patients underwent concomitant TIPS and transvenous obliteration in the same procedural setting. However, three patients underwent transvenous obliteration due to bleeding despite a patent TIPS that had been previously placed. The average time from TIPS placement to transvenous obliteration was 125 days (range: 3-324 days). After having both procedures, there was no rebleeding in the patients during a mean follow-up period of 22 months (6-50 months). Coils and/or metallic vascular plugs were used to augment the sclerosant obliteration in four of five patients. Conclusion: The combination of TIPS decompression and foam sclerosant transvenous obliteration appears to be effective in preventing rebleeding in this limited case series and compares favorably with the existing evidence for either approach [TIPS or balloon-occluded retrograde transvenous obliteration (BRTO)] alone.

PREAMBLE In recent years, the Society of Interventional Radiology (SIR) has become aware of a growing heterogeneity in the learning experiences of radiology trainees (residents and fellows) as it pertains to the subject of interventional radiology (IR). Unfortunately, the Accreditation Council for Graduate Medical Education (ACGME) program requirements are somewhat vague as to what constitutes adequate training in this field. Therefore, a task force was created to create guidelines for training in the field of IR. Task force members included physicians who practice in academic and private-practice settings. Also, the task force contained a cross-section of thought leaders in the various clinical realms of IR (peripheral arterial disease, interventional oncology, venous disease, interventional neuroradiology, and renal insufficiency). Many members are current or past program directors of diagnostic radiology (DR) residencies or IR fellowships. The guidelines put forth in this document are intended for the training of radiology residents and IR fellows in the knowledge base and technical skills related to minimally invasive interventional procedures. As part of this education, trainees must gain an appropriate depth of understanding of the disease states being treated and their clinical management to allow for optimal clinical outcomes. It is intended that program directors in DR residencies and program directors in vascular and IR (VIR) fellowships will use this document as a basis for the creation of program-specific curricula and goals and objectives documents for trainees. In addition, this document is intended for reference by radiology chairs, designated institutional officials, and deans so they may allocate appropriate resources to training programs to meet these training requirements. Finally, although training paradigms differ around the world, it is hoped that these guidelines will also be helpful in the creation of educational curricula for international IR programs as well. SIR recognizes that the multiple levels of trainees covered by this document will require differing experiences to meet their differing needs. For example, the DR trainee who is pursuing a career in a general radiology or in a diagnostic imaging subspecialty will not require the same training as a resident planning to enter into a VIR fellowship. Therefore, four separate sets of training requirements will be set forth in this document

Objectives: On completion of this article, the reader will be able to identify the pathophysiology, clinical presentation, treatment options, and outcomes of liver transplant recipients with arterioportal fistulas. Accreditation: Tufts University School of Medicine is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. Credit: Tufts University School of Medicine designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 Credit™. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Arterioportal fistulae (APFs) are classified into intrahepatic (>75% of all reported APFs) and extrahepatic ( 90%). Reportedly, all APFs in liver transplant recipients have been intrahepatic APFs.1,2,3 APFs are further classified into hemodynamically significant and hemodynamically insignificant. The determinant of hemodynamic significance is Doppler ultrasound findings suggestive of involvement of the main, right, or left portal vein.1,2,3,4 This article discusses APFs that are specific to liver transplant recipients. Their incidence, etiology, pathogenesis, natural history, clinical presentation, imaging evaluation, and endovascular management are discussed in detail.

Portal vein interventions in liver transplant recipients represent a group of interventions in the management of several disease entities including portal vein stenosis, portal vein thrombosis, and recurrent liver cirrhosis with portal hypertension with and without gastric varices. The procedures performed in these patient populations include portal vein angioplasty with or without stent placement for portal vein stenosis, portal vein thrombolysis with or without stent placement for portal vein thrombosis, transjugular intrahepatic portosystemic shunts or splenic embolization for cirrhosis, and balloon-occluded retrograde transvenous obliteration for gastric varices. This article discusses these disease entities and the minimal invasive procedures used in their management.