Current Controversies in Inferior Vena Cava Filter Placement: AJR Expert Panel Narrative Review.

Despite inferior vena cava (IVC) filter practice spanning over 50 years, interventionalists face many controversies in proper utilization and management. This article reviews recent literature and offers opinions on filter practices. IVC filtration is most likely to benefit patients at high risk of iatrogenic pulmonary embolus during endovenous intervention. Filters should be used selectively in patients with acute trauma or who are undergoing bariatric surgery. Retrieval should be attempted for perforating filter and fractured filter fragments when imaging suggests feasibility and favorable risk-to-benefit ratio. Antibiotic prophylaxis should be considered when removing filters with confirmed gastrointestinal penetration. Anticoagulation solely because of filter presence is not recommended except in patients with active malignancy. Anticoagulation while filters remain in place may decrease long-term filter complications in these patients. Patients with a filter and symptomatic IVC occlusion should be offered filter removal and IVC reconstruction. Physicians implanting filters may maximize retrieval by maintaining physician-patient relationships and scheduling follow-up at time of placement. Annual follow-up allows continued evaluation for removal or replacement as appropriate. Advanced retrieval techniques increase retrieval rates but require caution. Certain cases may require referral to experienced centers with additional retrieval resources. The views expressed should help guide clinical practice, future innovation, and research.

A Role for Virtual Reality in Planning Endovascular Procedures.

Current imaging technologies are capable of acquiring volumetric data, but they are limited by the flat 2-dimensional representation of complex 3-dimensional data. This pictorial report illustrates the potential role of interactive virtual reality (VR) that enables physicians to visualize and interact with image data as if they were real physical objects. Increasing availability of tools that make the VR environment a possibility could potentially be valuable in the interventional radiology suite.

Endovascular Removal of Fractured Inferior Vena Cava Filter Fragments: 5-Year Registry Data with Prospective Outcomes on Retained Fragments.

PURPOSE: To evaluate the safety and efficacy of attempted percutaneous filter fragment removal during retrieval of fractured inferior vena cava (IVC) filters and to report outcomes associated with retained filter fragments. MATERIALS AND METHODS: Over a 5-year period, 82 consecutive patients presenting with a fractured IVC filter were prospectively enrolled into an institutional review board-approved registry. There were 27 men and 55 women (mean, 47 y; range, 19-85 y). After main filter removal, percutaneous removal of fragments was attempted if they were deemed intravascular and accessible on preprocedural computed tomography (CT), cone-beam CT, and/or intravascular ultrasound; distal pulmonary artery (PA) fragments were left alone. A total of 185 fragments were identified (81 IVC, 33 PA, 16 cardiac, 2 hepatic vein, 1 renal vein, 1 aorta, 51 retroperitoneal). Mean filter dwell time was 2,183 days (range, 59-9,936 d). Eighty-seven of 185 fragments (47%) were deemed amenable to attempted removal: 65 IVC, 11 PA, 8 cardiac, 2 hepatic, and 1 aortic. Primary safety outcomes were major procedure-related complications. RESULTS: Fragment removal was successful in 78 of 87 cases (89.7%; 95% confidence interval [CI], 81.3-95.2). There were 6 minor complications with no consequence (6.9%; 95% CI, 2.6-14.4) involving intraprocedural fragment embolization and 1 major complication (1.1%; 95% CI, 0.0-6.2), a cardiac tamponade that was successfully treated. The complication rate from attempted cardiac fragment removal was 12.5% (1 of 8; 95% CI, 0.3-52.7). Among patients with retained cardiopulmonary fragments (n = 19), 81% remained asymptomatic during long-term clinical follow-up of 845 days (range, 386-2,071 d). CONCLUSIONS: Percutaneous removal of filter fragments from the IVC and proximal PAs is safe and effective overall, but attempted intracardiac fragment removal carries a higher risk of complication. Most residual filter fragments not amenable to percutaneous removal remain asymptomatic and may be monitored clinically.

Accuracy of Information Provided by ChatGPT Regarding Liver Cancer Surveillance and Diagnosis.

ChatGPT did not reliably provide accurate information to 20 questions about liver cancer surveillance and diagnosis, as assessed by six physicians who actively diagnose and/or treat liver cancer. Answers deemed inaccurate commonly related to questions on specific LI-RADS categories and included contradictory or falsely reassuring, if not wrong, information.

Building Radiology Equity: Themes from the 2023 RAD-AID Conference on International Radiology and Global Health.

Low- and middle-income countries are significantly impacted by the global scarcity of medical imaging services. Medical imaging is an essential component for diagnosis and guided treatment, which is needed to meet the current challenges of increasing chronic diseases and preparedness for acute-care response. We present some key themes essential for improving global health equity, which were discussed at the 2023 RAD-AID Conference on International Radiology and Global Health. They include (1) capacity building, (2) artificial intelligence, (3) community-based patient navigation, (4) organizational design for multidisciplinary global health strategy, (5) implementation science, and (6) innovation. Although not exhaustive, these themes should be considered influential as we guide and expand global health radiology programs in low- and middle-income countries in the coming years.

Implementation and Evaluation of a Comprehensive Simulation Curriculum for the IR/DR Integrated Residency.

RATIONALE AND OBJECTIVES: Endovascular simulation is a validated training method, allowing residents to improve technical skills with interventional equipment in a risk-free environment. The purpose of this study was to assess the utility and efficacy of supplementing the IR/DR Integrated Residency training program with a dedicated 2-year endovascular simulation curriculum. MATERIALS AND METHODS: Trainees participated in a 2-year curriculum that included the completion of 8 modules using a high-fidelity endovascular simulator (Mentice AB, Gothenberg, Sweden). Procedural modules included IVC filter placement, transarterial chemoembolization, trauma embolization, uterine artery embolization, prostate artery embolization, and peripheral arterial disease interventions. Each quarter, two trainees were filmed while completing an assigned module. Sessions led by IR faculty were held with film footage review and didactics on the assigned topic. Pre- and postcase surveys were collected to evaluate trainee comfort and confidence and assess the validity of the simulation. At the conclusion of the 2-year period, a postcurriculum survey was sent to all trainees to determine how residents viewed the utility of the simulation sessions. RESULTS: Eight residents participated in the pre- and postcase surveys. The simulation curriculum significantly increased trainee confidence for these 8 residents. A separate postcurriculum survey was completed by all 16 IR/DR residents. All 16 residents felt that simulation was a helpful addition to their education. A total of 87.5% of all residents felt that the sessions improved their confidence in the IR procedure room. A total of 75% of all residents believe that the simulation curriculum should be incorporated into the IR residency program. CONCLUSION: Adoption of a 2-year simulation curriculum can be considered for existing IR/DR training programs with access to high-fidelity endovascular simulators using the described approach.

Performance of RAPID noncontrast CT stroke platform in large vessel occlusion and intracranial hemorrhage detection.

Background: Noncontrast CT (NCCT) is used to evaluate for intracerebral hemorrhage (ICH) and ischemia in acute ischemic stroke (AIS). Large vessel occlusions (LVOs) are a major cause of AIS, but challenging to detect on NCCT. Aims: The purpose of this study is to evaluate an AI software called RAPID NCCT Stroke (RAPID, iSchemaView, Menlo Park, CA) for ICH and LVO detection compared to expert readers. Methods: In this IRB approved retrospective, multicenter study, stand-alone performance of the software was assessed based on the consensus of 3 neuroradiologists and sensitivity and specificity were determined. The platform's performance was then compared to interpretation by readers comprised of eight general radiologists (GR) and three neuroradiologists (NR) in detecting ICH and hyperdense vessel sign (HVS) indicating LVO. Results: A total of 244 cases were included. Of the 244, 115 were LVOs and 26 were ICHs. One hundred three cases did not have LVO nor ICH. Stand-alone performance of the software demonstrated sensitivities and specificities of 96.2 and 99.5% for ICH and 63.5 and 95.1% for LVO detection. Compared to all 11 readers and eight GR readers only respectively, the software demonstrated superiority, achieving significantly higher sensitivities (63.5% versus 43.6%, p < 0.0001 and 63.5% versus 40.9%, p = 0.001). Conclusion: The RAPID NCCT Stroke platform demonstrates superior performance to radiologists for detecting LVO from a NCCT. Use of this software platform could lead to earlier LVO detection and expedited transfer of these patients to a thrombectomy capable center.

Redefining Intermediate-Stage HCC Treatment in the Era of Immune Therapies.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. At diagnosis, most patients are ineligible for curative surgery, and approximately 20% of patients are diagnosed with advanced-stage disease. A significant proportion of patients fall under an unresectable or intermediate-stage disease who have liver-limited disease but are not surgical candidates because of large tumor size, number of lesions, or technically inoperable disease. In this unique intermediate-stage patient population, locoregional therapies have been the de facto mainstay of treatment because of high local response rates and favorable safety profile, especially in the context of minimally effective systemic therapies. However, not all patients who receive locoregional therapy for incurable disease have improved survival, and importantly, some of these patients never receive systemic therapy because of disease progression or further decline in hepatic function. Meanwhile, with the remarkable progress that has been made with systemic therapy in the past few years, revisiting the treatment of intermediate-stage HCC seems prudent. In this review, we will highlight current and emerging strategies for treating patients with unresectable, liver-limited HCC.

Safety and Efficacy of Microwave Ablation for Hepatocellular Carcinoma in the Setting of Transjugular Intrahepatic Portosystemic Shunt.

This retrospective analysis reviews five patients with transjugular intrahepatic portosystemic shunt (TIPS) who underwent percutaneous microwave ablation of hepatocellular carcinoma between January 2017 and September 2020. Mean tumor diameter was 2.0 cm (range 1.3-2.9 cm), and mean tumor distance from TIPS was 2.3 cm (range 1.5-3.3 cm). There were no major adverse events, and the TIPS patency was 100% post-ablation. The technical success rate was 100%, and the complete response rate was 100%. In this small study, percutaneous microwave ablation appears safe and effective for the treatment of hepatocellular carcinoma in patients with TIPS in the short-term follow-up period.

Transjugular intrahepatic portosystemic shunt (TIPS) as rescue therapy for endoscopic glue migration and bleeding gastric varices.

Gastric variceal (GV) bleeding is an important and fatal complication for cirrhotic patients which has historically been controlled with sclerosants and band ligation. Cyanoacrylate glue therapy has emerged as a more favorable option with bleeding control of up to 90% and low complication rates; however, several reports show possible ectopic systemic glue migration, most commonly into the portomesenteric system and leading to portal hypertension. To decompress portal pressures and mitigate future complications, transjugular intrahepatic portosystemic shunt (TIPS) placement may be a viable rescue therapy. We present two cases of TIPS placement for an 18-year-old and 51-year-old male in the setting of endoscopic glue migration into the portomesenteric system that demonstrate feasibility and success in temporizing acute variceal bleeding. Both cases demonstrated decompressing portovenous pressures but may result in need for re-intervention.

Prevalence of hypercoagulable states in stented thrombotic iliac vein compression syndrome with comparison of re-intervention and anticoagulation regimens.

BACKGROUND: Endovascular therapy is playing an increasing role in the treatment of iliofemoral venous disease. Iliac stent patency is multifactorial, and current management is based on best clinical practices, varying by institution. AIM: To evaluate how thrombophilia influences management and outcomes of patients who undergo venous stenting for thrombotic iliac vein compression syndromes. METHODS: A retrospective observational analysis was performed on 65 patients with thrombotic iliac vein compression syndrome that underwent common iliac vein (CIV) stenting between December 2013 and December 2019 at a large academic center. Search criteria included CIV stenting and iliac vein compression. Non-thrombotic lesions and iliocaval thrombosis and/or occlusions were excluded. A total of 65 patients were selected for final analysis. Demographic information, procedural data points, and post-procedural management and outcomes were collected. Statistical analyses included Fisher's exact and Chi-square tests to compare discrete variables and the Wilcoxon rank-sum test to compare continuous variables between thrombophilia positive and negative patients. RESULTS: 65 patients underwent successful balloon angioplasty and CIV stenting. Of these patients, 33 (50.8%) underwent thrombophilia testing, with 16 (48.5%) testing positive. Stent patency on ultrasound did not significantly differ between thrombophilia positive and negative patients at 1 mo (92.3% vs 81.3%, P = 0.6), 6 mo (83.3% vs 80%, P > 0.9), or 12 mo (77.8% vs 76.9%, P = 0.8). Immediately after stent placement, thrombophilia patients were more likely to be placed on dual therapy (aspirin and anticoagulation) or triple therapy (aspirin, clopidogrel, and anticoagulation) (50% vs 41.2%, P > 0.9), and remain on dual therapy at 6 mo (25% vs 12.5%, P = 0.5) and 12 mo (25% vs 6.7%, P = 0.6). There was no significant difference in re-intervention rates (25% vs 35.3%, P = 0.7) or number of re-interventions (average 2.3 vs 1.3 per patient, P = 0.4) between thrombophilia positive and negative patients. CONCLUSION: Half of patients with stented thrombotic iliac vein compression syndrome and thrombophilia testing were positive. The presence of thrombophilia did not significantly impact stent patency or re-intervention rates.

Role of interventional radiology in the treatment of COVID-19 patients: Early experience from an epicenter.

OBJECTIVE: To highlight the role of interventional radiology (IR) in the treatment of patients hospitalized with coronavirus disease 2019 (COVID-19). METHODS: Retrospective review of hospitalized patients who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and had one or more IR procedures at a tertiary referral hospital in New York City during a 6-week period in April and May of 2020. RESULTS: Of the 724 patients admitted with COVID-19, 92 (12.7%) underwent 124 interventional radiology procedures (79.8% in IR suite, 20.2% at bedside). The median age of IR patients was 63 years (range 24-86 years); 39.1% were female; 35.9% in the intensive care unit. The most commonly performed IR procedures were central venous catheter placement (31.5%), inferior vena cava filter placement (9.7%), angiography/embolization (4.8%), gastrostomy tube placement (9.7%), image-guided biopsy (10.5%), abscess drainage (9.7%), and cholecystostomy tube placement (6.5%). Thoracentesis/chest tube placement and nephrostomy tube placement were also performed as well as catheter-directed thrombolysis of massive pulmonary embolism and thrombectomy of deep vein thrombosis. General anesthesia (10.5%), monitored anesthesia care (18.5%), moderate sedation (29.8%), or local anesthetic (41.1%) was utilized. There were 3 (2.4%) minor complications (SIR adverse event class B), 1 (0.8%) major complication (class C), and no procedure-related death. With a median follow-up of 4.3 months, 1.1% of patients remain hospitalized, 16.3% died, and 82.6% were discharged. CONCLUSION: Interventional radiology participated in the care of hospitalized COVID-19 patients by performing a wide variety of necessary procedures.

Interreader Variability in Semantic Annotation of Microvascular Invasion in Hepatocellular Carcinoma on Contrast-enhanced Triphasic CT Images.

Purpose: To evaluate interreader agreement in annotating semantic features on preoperative CT images to predict microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC). Materials and Methods: Preoperative, contrast material-enhanced triphasic CT studies from 89 patients (median age, 64 years; age range, 36-85 years; 70 men) who underwent hepatic resection between 2008 and 2017 for a solitary HCC were reviewed. Three radiologists annotated CT images obtained during the arterial and portal venous phases, independently and in consensus, with features associated with MVI reported by other investigators. The assessed factors were the presence or absence of discrete internal arteries, hypoattenuating halo, tumor-liver difference, peritumoral enhancement, and tumor margin. Testing also included previously proposed MVI signatures: radiogenomic venous invasion (RVI) and two-trait predictor of venous invasion (TTPVI), using single-reader and consensus annotations. Cohen (two-reader) and Fleiss (three-reader) κ and the bootstrap method were used to analyze interreader agreement and differences in model performance, respectively. Results: Of HCCs assessed, 32.6% (29 of 89) had MVI at histopathologic findings. Two-reader agreement, as assessed by pairwise Cohen κ statistics, varied as a function of feature and imaging phase, ranging from 0.02 to 0.6; three-reader Fleiss κ varied from -0.17 to 0.56. For RVI and TTPVI, the best single-reader performance had sensitivity and specificity of 52% and 77% and 67% and 74%, respectively. In consensus, the sensitivity and specificity for the RVI and TTPVI signatures were 59% and 67% and 70% and 62%, respectively. Conclusion: Interreader variability in semantic feature annotation remains a challenge and affects the reproducibility of predictive models for preoperative detection of MVI in HCC.Supplemental material is available for this article.© RSNA, 2020.

Endovascular simulation as a supplemental training tool during the COVID-19 national emergency.

The ongoing COVID pandemic raises many concerns as our healthcare system is pushed to its limits and as a consequence, Interventional Radiology training may be compromised. Endovascular simulators allow trainees many benefits to build and maintain endovascular skills in a safe environment. Our experience demonstrates a methodology to maintain IR training with use of didactic and simulation supplementation during the COVID-19 pandemic, which may be helpful for incorporation at other institutions facing similar challenges.