Percutaneous Ultrasound-Guided Kidney Transplant Biopsy Outcomes: From the Nephrologist to the Radiologist Standpoint.

Background: Kidney transplant biopsies are the gold standard for evaluating allograft dysfunction. These biopsies are performed by nephrologists and radiologists under real-time ultrasound guidance. A few studies have examined the outcomes of ultrasound-guided kidney transplant biopsy in transplant recipients; however, none have compared these outcomes between both specialties. Methods: We retrospectively analyzed a cohort of 678 biopsies performed in a single center during a 44-month study period. Biopsies were stratified into two groups based upon the specialist performing the procedure: interventional radiology (IR; N=447) and transplant nephrology (TN; N=231). Results: There were 55 (8%) complications related to biopsies in the entire cohort: 37 (8.2%) in the IR group and 18 (7.7%) in the TN group, without statistical difference between the groups (P=0.94). Blood pressure control and prior use of anticoagulation were significant predictors of complicated biopsies (P=0.004 and 0.02, respectively). Being a woman and prior use of anticoagulation were significant predictors of transfusion of blood products (P=0.01 and 0.01, respectively). Being a woman and blood pressure control were significant predictors of overall perinephric hematoma (P=0.01 and 0.01, respectively), and Black race was a significant predictor of perinephric hematoma without worsening of renal function (P=0.005). The specialist team performing the procedure was not a statistically significant predictor of biopsy complications, transfusion of blood products, or perinephric hematoma with comparable sample yield. Conclusions: Percutaneous ultrasound-guided kidney transplant biopsy performed by transplant nephrologists have similar complication rates when compared with interventional radiologists in an academic center.

Emergent mechanical thrombectomy for right atrial clot and massive pulmonary embolism using flowtriever.

This case demonstrated a feasible alternative to treat "clot in transit" associated with pulmonary embolism using FlowTriever Inari device. The pre-existing approved AngioVac device requires extracorporeal circulation support and more invasiveness. FlowTriever permits mechanical thrombectomy with versatile approach without additional extracorporeal perfusion setting. Additional studies are required to reach a definitive conclusion.

Impact of liver-directed therapy and non-therapy on the waiting time list of patient candidates for liver transplantation: retrospective survival analysis.

AIM OF THE STUDY: To determine whether liver-directed therapies (LDT) and no therapy affect waiting list times for liver transplant candidates from a single center. MATERIAL AND METHODS: This retrospective study included patients > 12 years of age diagnosed with hepatocellular carcinoma between January 2014 and June 2019 and followed until the date of transplant, date of delisting, loss to follow-up, or date of death. Waiting list time and associated factors were analyzed using Kaplan-Meier and Cox proportional-hazards methods. RESULTS: A total of 181 patients met the selection criteria. The mean age was 60 years with standard deviation (SD) of 7.8 years. Sixty-six percent underwent transplant, and 64% were classified within the Milan criteria. Men had a lower median waiting list time than women (191 days vs. 236 days, p = 0.0093). The overall median survival time or time to transplant for 50% of the population was 218 days (95% CI: 195-235). Men displayed a 3.1-fold (95% CI: 1.5-6.2) higher probability of transplantation than women (p = 0.002). Patients who received no therapy had a 5-fold higher probability of undergoing transplantation than patients under arterial LDT (HR [95% CI]: 5 [1.2, 20], p = 0.02). Patients under combined LDT displayed a 70% reduced probability of transplantation compared to patients who received arterial LDTs (p = 0.0009). CONCLUSIONS: LDT was associated with a prolonged stay on the transplant list, likely due to the presence of an aggressive liver tumor. However, LDTs allow the patient to remain active on the liver transplant list, increasing their chances of undergoing transplantation.

Computed Tomography-Guided Kidney Transplant Biopsy Outcomes: A Single-Center Experience.

OBJECTIVES: Percutaneous kidney transplant biopsy is typically performed using ultrasonographic guidance; computed tomography is an alternative modality used to obtain kidney allografttissuewhen ultrasonographyguided percutaneous kidney transplant biopsy is technically challenging. Studies examining postbiopsy outcomes in kidney transplant patients using a computed tomography-guided approach are scarce. Our goal was to reportthe incidence of nonsevere and severe complications in computed tomographyguided percutaneous kidney transplant biopsies and the potential risk factors. MATERIALS AND METHODS: We retrospectively reviewed computed tomography-guided percutaneous kidney transplant biopsies in patients undergoing work-up for kidney allograft rejection between 2013 and 2017. Demographics, comorbidities, laboratory data, history of antiplatelet and/or anticoagulant use, and complications were assessed. RESULTS: : During the study period, 28 patients underwent computed tomography-guided percutaneous kidney transplant biopsies; mean age was 57.5 ± 15.5 years, and 12 (43%)werewomen.Twenty-three patients (82%) were obese, with a body mass index greater than 30 kg/m². Our cohort of kidney transplant recipients included 21 (75%) from deceased donors and 7 (25%) from living-related donors. At the time of biopsy, 6 patients (21%) had elevated blood pressure (defined as > 160/90 mm Hg). One patient had severe complications, which included a significant decrease in hemoglobin requiring transfusion and a perinephric hematoma with worsening renal function. This was a morbidly obese patient whose blood pressure was elevated at the time of biopsy with a platelet count of 93 × 10³/mm³ and international normalized ratio of 1.21. CONCLUSIONS: A computed tomography-guided percutaneous kidney transplant biopsy is a safe and effective alternative to obtain kidney tissue in the obese population and is associated with low rates of complications. In this study, we highlighted the need to achieve adequate blood pressure control and assess bleeding risk factors, such as platelet count and international normalized ratio, prior to biopsy.

Discovery of a spontaneous portosystemic shunt following portal vein embolization.

INTRODUCTION: Right portal vein embolization (PVE) has become a crucially important option in the minimally-invasive treatment of hepatocellular carcinoma or secondary liver malignancy before partial hepatectomy or trisegmentectomy to reduce perioperative morbidity. The main goal of PVE is to increase the volume of the future liver remnant (FLR), which can provide complete liver metabolic functionality without risk of developing posthepatectomy liver failure, also known as "small for size syndrome." PVE accomplishes this via the redirection of portal venous flow toward the left portal vein circulation resulting in an increased left hepatic lobe volume. CASE REPORT: We present a patient with a noncirrhotic liver and a previously unknown portal venous to systemic venous shunt that became apparent after a right PVE was completed. Left untreated, this shunt would have undoubtedly jeopardized the FLR volume. CONCLUSION: The presence of previously undetected portosystemic shunting is a potential cause for otherwise assumed idiopathic PVE failure, and the goal of this article is to underscore the importance of evaluating for these shunts before PVE.

Utilization of a Modified Roux-en-Y Anastomosis as an Access point for Percutaneous Transjejunal Cholangioplasty of Recurrent Biliary Strictures.

INTRODUCTION: Biliary duct injuries pose a significant management challenge due to the propensity for recurrent biliary strictures. Development of a modified Roux-en-Y hepaticojejunostomy known as a Hutson-Russell Pouch (HRP) provides a point of entry for repetitive access to the biliary tree. We aim to highlight the effectiveness of using the HRP as an access point for the long-term management of anastomotic and distal biliary strictures, thereby showcasing the value in potential widespread adoption of this modification to a standard surgical procedure. MATERIALS AND METHODS: IRB-approved retrospective study of 36 patients (10 M, 26 F; mean age 55.19 ± 13.94; 15-83) underwent a total of 110 transjejunal cholangiograms. Indications for cholangiogram included cholangitis (n = 38), surveillance (n = 36), and elevated liver enzymes (n = 36). Technical success was defined by the ability to access and intervene in the biliary tree via HRP access. In case of stenosis, the ability to successfully dilate (< 30%) residual stenosis was considered a technically successful procedure. Clinical success was defined by normalization of the liver function tests or resolution of cholangitis. RESULTS: Technical success was achieved in 83/110 (75.45%) of the cases, and clinical success was achieved in 102/110 (98.2%). Transhepatic access was needed in 27/110 (24.5%) of the cases. Interventions performed included balloon cholangioplasty in 104/110 (94.5%), biliary stone removal in 2/110 (1.8%), biliary stent placement in 2/110 (1.8%), and biliary drain placement in 4/110 (3.6%). There were a total of 9/110 complications (8.2%). CONCLUSION: The HRP was an effective access point in the management of recurrent benign biliary strictures in this cohort.

Visceral arterial embolization prior to multivisceral transplantation in recipient with cirrhosis, extensive portomesenteric thrombosis, and hostile abdomen: Performance and outcome analysis.

Multivisceral transplant (MVT) for cirrhosis, and portomesenteric vein thrombosis (PVT), is fraught with life-threatening thrombo-hemorrhagic complications. Embolization of native viscera has been attempted in a handful of cases with mixed results. We carried out a comparative analysis of angiographic, intra-operative, and pathological findings in three recipients of MVT who were deemed exceptionally high hemorrhagic risk and therefore underwent preoperative visceral embolization. All recipients were male with cirrhosis, PVT, and a surgical history indicative of diffuse visceral adhesions; status post-liver transplantation (n = 2) and proctocolectomy (n = 1). The first patient had two Amplatzer II embolization plugs placed 2 cm from the origins of celiac and superior mesenteric (SMA) arteries. Distal migration of the celiac plug into gastroduodenal artery (GDA) and ensuing ischemia reperfusion injury, presumably contributed to severe disseminated intravascular coagulation (DIC) and intra-operative mortality. In the other two recipients, distal Gelfoam embolization of the SMA, GDA, and splenic arteries was performed, and although remarkable hemorrhage and coagulopathy occurred, embolization, undoubtedly, facilitated exenteration and improved outcomes. Pathologic examination in these cases confirmed ischemic necrosis of eviscerated bowel. In conclusion, liver-sparing, preoperative distal embolization of native viscera with Gelfoam is beneficial, but entails several pitfalls. It should currently be reserved for MVT recipients who otherwise are at unacceptably high risk.

High-Fidelity Endovascular Simulation.

With the ongoing changes in graduate medical education, emphasis has been placed on simulation models to increase clinical exposure and optimize learning. In specific, high-fidelity simulation presents as a potential option for procedural-skill development in interventional radiology. With improved haptic, visual, and tactile dynamics, high-fidelity endovascular simulators have gained increasing support from trainees and certified interventionalists alike. The 2 most common high-fidelity endovascular simulators utilized today are the Procedicus VIST and ANGIO Mentor, which contain notable differences in technical features, case availability, and cost. From the perspective of a trainee, high-fidelity simulation allows for the ability to perform a greater volume of cases. Additionally, without the risk of potential harm to the patient, trainees can focus on repetition and improved performance in a stress-free environment. When errors are made, high-fidelity simulator metrics will generate instantaneous feedback and error notification, erasing ambiguity and thus facilitating learning. Furthermore, in an environment devoid of time and cost stressors, the supervising physician is afforded the opportunity to properly mentor and instruct the trainee throughout the case. For the experienced interventionalists, high-fidelity simulation allows for a decreased learning curve for new procedures or techniques, as well as the opportunity for procedure rehearsal for unusual or high-risk cases. Despite the limitations created by cost, high-fidelity endovascular simulation should continue to be increasingly utilized in the development of the interventional radiology curriculum.

A Venous Malformation in the Vastus Lateralis: Our Experience with Cryotherapy.

The present report describes a case of cryotherapy ablation in a 35-year-old woman with a 1.5 cm painful venous malformation (VM) in the right vastus lateralis muscle. After the patient had failed sclerotherapy, a single session of cryotherapy was performed that resulted in both technical and clinical success. At 8-month follow-up, there was no residual pain. The use of cryotherapy ablation for the treatment of an intramuscular VM has only been previously described on 1 occasion. Based on our results, cryotherapy is a promising therapy for fast and safe treatment for patients with venous vascular malformations.

Percutaneous Retrieval of IVC Filters With Struts Penetrating the Vertebral Body.

INTRODUCTION: Inferior vena cava (IVC) filter penetration of the caval wall is a well-documented complication. Less frequently, the struts of an IVC filter can penetrate a vertebral body that can lead to symptoms of abdominal pain. Vertebral penetration poses a management challenge, and characteristics for successful endovascular retrieval of such filters has not been reported. CASE DESCRIPTION: We present 2 cases of IVC filters with vertebral body penetration that were successfully retrieved through an endovascular approach. On preprocedure computed tomography, both patients had a small zone of osteolysis surrounding the penetrated struts into the vertebral body. The procedures were done via right internal jugular access using an Ensnare device. In one of the cases, the hangman technique was used to release the filter apex from the vessel wall. Both filters were able to be retrieved without using excessive force, follow-up venacavograms showed no sign of extravasation, and no postprocedure complications developed. DISCUSSION: Preprocedure CT imaging is essential prior to IVC filter removal if vertebral penetration is suspected. The zone of osteolysis seen around the struts in both cases are likely the result of constant cardiorespiratory motion of the filter. Based on the fact that in both cases the filter legs were able to be disengaged from the vertebral body without the use of excessive force, we hypothesize that if a zone of osteolysis surrounding the struts can be confirmed on preprocedural CT, the filter removal can be safely attempted by the standard percutaneous endovascular approach.

Transjugular intrahepatic portosystemic shunt for chylous ascites in a patient with recurrent cirrhosis following liver transplantation.

Chylous ascites (CA) is the extravasation of lipid-rich lymphatic fluid into the peritoneal space following trauma or obstruction of the lymphatic system. Refractory cases of cirrhosis-related CA may be amendable to transjugular intrahepatic portosystemic shunting (TIPS). We present a case of TIPS in the setting of refractory CA secondary to cirrhosis of a transplanted liver graft. Following TIPS, the patient reported immediate improvement in abdominal pain and no longer requires paracentesis. Our case suggests TIPS to be a safe and effective treatment option for CA in liver transplant patients with cirrhosis.

Transarterial embolization of a hyperfunctioning aldosteronoma in a patient with bilateral adrenal nodules.

Primary hyperaldosteronism often results in resistant hypertension and hypokalemia, which may lead to cardiovascular and cerebrovascular complications. Although surgery is first line treatment for unilateral functioning aldosteronomas, minimally invasive therapies may be first line for certain patients such as those who cannot tolerate surgery. We present a case of transarterial embolization (TAE) of an aldosteronoma. The patient presented with a cerebrovascular accident, and subsequently developed uncontrolled hypertension, hypokalemia, and a myocardial infarction. Following TAE, potassium returned to normal levels and blood pressure control was improved. There were no postoperative complications. TAE thus may be a safe and effective alternative to surgery.

Transsplenic portal vein reconstruction-transjugular intrahepatic portosystemic shunt in a patient with portal and splenic vein thrombosis.

Portal vein thrombosis (PVT) is a potential complication of cirrhosis and can worsen outcomes after liver transplant (LT). Portal vein reconstruction-transjugular intrahepatic portosystemic shunt (PVR-TIPS) can restore flow through the portal vein (PV) and facilitate LT by avoiding complex vascular conduits. We present a case of transsplenic PVR-TIPS in the setting of complete PVT and splenic vein (SV) thrombosis. The patient had a 3-year history of PVT complicated by abdominal pain, ascites, and paraesophageal varices. A SV tributary provided access to the main SV and was punctured percutaneously under ultrasound scan guidance. PV access, PV and SV venoplasty, and TIPS placement were successfully performed without complex techniques. The patient underwent LT with successful end-to-end anastomosis of the PVs. Our case suggests transsplenic PVR-TIPS to be a safe and effective alternative to conventional PVR-TIPS in patients with PVT and SV thrombosis.

Amplatzer vascular plug as an embolic agent in different vascular pathologies: A pictorial essay.

The Amplatzer Vascular Plug (AVP) is a cylindrical plug made of self-expanding nitinol wire mesh with precise delivery control, which can be used for a variety of vascular pathologies. An AVP is an ideal vascular occlusion device particularly in high-flow vessels, where there is high risk of migration and systemic embolization with traditional occlusion devices. We performed 28 embolizations using the AVP from 2009 to 2014 and achieved complete occlusion without complications.