Percutaneous Chemical and Mechanical Necrosectomy for Walled-Off Pancreatic Necrosis.

PURPOSE: To test the hypothesis that percutaneous combined chemical and mechanical necrosectomy using a Malecot anchor drain and an Arrow-Trerotola percutaneous thrombolytic device (PTD) in patients with walled-off pancreatic necrosis (WOPN) is feasible, safe, and effective compared with a control group undergoing mechanical necrosectomy alone. MATERIALS AND METHODS: In a retrospective analysis, patients with WOPN not amenable to endoscopic-guided cystogastrostomy placement were studied as case and control groups. The patients in the case group underwent percutaneous combined chemical (hydrogen peroxide 3%) and mechanical necrosectomy using a Malecot anchor drain and/or Arrow-Trerotola PTD from December 2020 to April 2022. The controls underwent mechanical necrosectomy alone without chemical necrosectomy. Clinical success was defined as complete resolution of the cavity on follow-up noncontrast computed tomography scans with subsequent drain removal. RESULTS: Thirteen patients in the case group and 11 patients in the control group underwent percutaneous drain placement followed by percutaneous combined chemical and mechanical necrosectomy (case group) or mechanical necrosectomy only (control group) for WOPN. Drain placement and necrosectomy were technically successful in all patients studied. One patient in the case group developed postprocedural sepsis because of communication between the cavity and the splenic vein. Another patient in the case group developed bleeding from a branch of the pancreaticoduodenal artery on postnecrosectomy day 9, which was successfully embolized by interventional radiology. No pancreaticocutaneous fistula was reported at the 3-month follow-up. The clinical success rates in the case and control groups were 100% and 38.4%, respectively (P = .003). CONCLUSIONS: Percutaneous combined chemical and mechanical necrosectomy is a feasible, safe, and effective treatment of WOPN.

Contemporary Management of Blunt Liver Trauma: An Analysis of the Trauma Quality Improvement Program Registry (2007-2019).

PURPOSE: To evaluate the effectiveness of management strategies for blunt liver injuries in adult patients. MATERIALS AND METHODS: Patients aged ≥18 years with blunt liver injuries registered via the Trauma Quality Improvement Program (2007-2019) were identified. Management strategies initiated within 24 hours of hospital presentation were classified as nonoperative management (NOM), embolization, surgery, or combination therapy. Patients were stratified by injury grade. Linear models estimated each strategy's effect on hospital length of stay (LOS), intensive care unit (ICU) LOS, ventilator dependence, and mortality. RESULTS: Of 78,127 included patients, 88.7%, 8.7%, 1.8%, and 0.8% underwent NOM, surgery, embolization, and combination therapy, respectively. Among patients with low-grade (n = 62,237) and high-grade (n = 15,890) injuries and compared with all other management strategies, NOM was associated with the shortest hospital LOS and ICU LOS. Among patients with low-grade injuries and compared with surgery, embolization was associated with a shorter hospital LOS (9.7 days; P < .001; Cohen d = 0.32) and ICU LOS (5.3 days; P < .001; Cohen d = 0.36). Among patients with high-grade injuries and compared with surgery, embolization was associated with a shorter ICU LOS (6.0 days; P < .01; Cohen d = 0.24). Among patients with low- and high-grade injuries and compared with embolization, surgery was associated with higher odds of mortality (P < .001). CONCLUSIONS: Among patients presenting with blunt liver injuries and compared with surgery, embolization was associated with a shorter ICU LOS and lower risk of mortality.

Utilization and Comparative Effectiveness of Uterine Artery Embolization versus Hysterectomy for Severe Postpartum Hemorrhage: A National Inpatient Sample Study.

PURPOSE: To identify differences in mortality or length of hospital stay for mothers treated with uterine artery embolization (UAE) or hysterectomy for severe postpartum hemorrhage (PPH), as well as to analyze whether geographic or clinical determinants affected the type of therapy received. MATERIALS AND METHODS: This National Inpatient Sample study from 2005 to 2017 included all patients with live-birth deliveries. Severe PPH was defined as PPH that required transfusion, hysterectomy, or UAE. Propensity score weighting-adjusted demographic, maternal, and delivery risk factors were used to assess mortality and prolonged hospital stay. RESULTS: Of 9.8 million identified live births, PPH occurred in 31.0 per 1,000 cases. The most common intervention for PPH was transfusion (116.4 per 1,000 cases of PPH). Hysterectomy was used more frequently than UAE (20.4 vs 12.9 per 1,000 cases). The following factors predicted that hysterectomy would be used more commonly than UAE: previous cesarean delivery, breech fetal position, placenta previa, transient hypertension during pregnancy without pre-eclampsia, pre-existing hypertension without pre-eclampsia, pre-existing hypertension with pre-eclampsia, unspecified maternal hypertension, and gestational diabetes (all P < .001). Delivery risk factors associated with greater utilization of hysterectomy over UAE included postterm pregnancy, premature rupture of membranes, cervical laceration, forceps vaginal delivery, and shock (all P < .001). There was no difference in mortality between hysterectomy and UAE. After balancing demographic, maternal, and delivery risk factors, the odds of prolonged hospital stay were 0.38 times lower with UAE than hysterectomy (P < .001). CONCLUSIONS: Despite similar mortality and shorter hospital stays, UAE is used far less than hysterectomy in the management of severe PPH.

Interventional Management of Acquired Lymphatic Disorders.

The lymphatic system is a complex network of tissues, vessels, and channels found throughout the body that assists in fluid balance and immunologic function. When the lymphatic system is disrupted related to idiopathic, iatrogenic, or traumatic disorders, lymphatic leaks can result in substantial morbidity and/or mortality. The diagnosis and management of these leaks is challenging. Modern advances in lymphatic imaging and interventional techniques have made radiology critical in the multidisciplinary management of these disorders. The authors provide a review of conventional and clinically relevant variant lymphatic anatomy and recent advances in diagnostic techniques such as MR lymphangiography. A detailed summary of technical factors related to percutaneous lymphangiography and lymphatic intervention is presented, including transpedal and transnodal lymphangiography. Traditional transabdominal access and retrograde access to the central lymph nodes and thoracic duct embolization techniques are outlined. Newer techniques including transhepatic lymphangiography and thoracic duct stent placement are also detailed. For both diagnostic and interventional radiologists, an understanding of lymphatic anatomy and modern diagnostic and interventional techniques is vital to the appropriate treatment of patients with acquired lymphatic disorders. ©RSNA, 2022.

Predictors of Survival after Yttrium-90 Radioembolization of Chemotherapy-Refractory Hepatic Metastases from Breast Cancer.

PURPOSE: To determine predictors of survival after transarterial radioembolization of hepatic metastases from breast cancer. MATERIALS AND METHODS: Twenty-four patients with chemotherapy-refractory hepatic metastases from breast cancer who underwent radioembolization from 2013 to 2018 were evaluated based on various demographic and clinical factors before and after treatment. Overall survival (OS) was estimated by Kaplan-Meier method. Log-rank analysis was performed to determine predictors of prolonged OS from the time of first radioembolization and first hepatic metastasis diagnosis. RESULTS: Median OS times were 35.4 and 48.6 months from first radioembolization and time of hepatic metastasis diagnosis, respectively. Radioembolization within 6 months of hepatic metastasis diagnosis was a positive predictor of survival from first radioembolization, with median OS of 38.9 months vs 22.1 months for others (P = .033). Estrogen receptor (ER)-positive status predicted prolonged survival (38.6 months for ER+ vs 5.4 months for ER-; P = .005). The presence of abdominal pain predicted poor median OS: 12.8 months vs 38.6 months for others (P < .001). The presence of ascites was also a negative predictor of OS (1.7 months vs 35.4 months for others; P = .037), as was treatment-related grade ≥ 2 toxicity at 3 months (5.4 months vs 38.6 months for others; P = .017). CONCLUSIONS: In patients with metastatic breast cancer, radioembolization within 6 months of hepatic metastasis diagnosis and ER+ status appear to be positive predictors of prolonged survival. Conversely, baseline abdominal pain, baseline ascites, and treatment-related grade ≥ 2 toxicity at 3 months after treatment appear to be negative predictors of OS.

Transvenous Biopsy in the Diagnosis of Intravascular or Perivascular Neoplasm: A Single-Center Retrospective Analysis of 36 Patients.

Between September 2008 and August 2017, 36 patients (mean age 56 y; range, 30-89 y) underwent transvenous biopsy of suspected tumor thrombus or perivascular tumor. Intravascular biopsy was pursued because of inaccessible percutaneous access in 9 patients (25%) and as part of a planned revascularization procedure in 27 patients (75%). Histopathologic results showed malignancy in 26 patients (72%) and benign etiologies in 10 patients (28%). No patients required repeat biopsy. There were no complications related to the biopsy procedure. The present series suggests that transvenous biopsy is a safe and accurate method of intravascular and perivascular mass tissue sampling.

The resuscitative endovascular balloon occlusion of aorta (REBOA) device-what radiologists need to know.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a novel device approved by the Food and Drug administration (FDA) in 2017 as an alternative to resuscitative emergent thoracotomy (RET). Due to advancements in placement of REBOA, including newly validated placement using anatomic landmarks, REBOA is now widely used by interventional radiologists and emergency physicians in acute subdiaphragmatic hemorrhage. Increased use of REBOA necessitates that radiologists are familiar with verification of proper REBOA placement to minimize complications. This review describes the REBOA device, indications, placement, and complications, summarizing the current available literature.

Thoracic Duct Embolization: Analysis of Practice Patterns.

BACKGROUND: Thoracic duct embolization (TDE) has become the standard treatment for atraumatic and traumatic chylothoraces. Numerous approaches to embolization including intranodal lymphangiography, transabdominal, and retrograde catheterization of the thoracic duct have become the preferred methods for the treatment of chyle leaks. The purpose of this study was to determine training, treatment techniques, outcomes, and practice patterns of practitioners performing TDE. METHODS: From September to October of 2017, a 34-question survey focusing on training, treatment techniques, outcomes, and practice patterns of TDE was distributed through the Open Forum of the Society of Interventional Radiology Connect website. Fifty-four practitioners completed the entire survey. Percentages were calculated for answers to the questions. Chi-squared analysis was performed, comparing data from academic center respondents, private practice settings, and hybrid practice settings. P values < 0.5 were considered statistically significant. RESULTS: All responses were from interventional radiologists. Forty-seven practitioners (87.0%) performed TDE in the United States, and 1 performed (1.9%) abroad; 6 practitioners (11.1%) did not perform TDE. Of all, 88.9% (n = 48) performed TDE in academic (n = 24; 50%), private (n = 17; 35.4%), or hybrid (n = 6; 12.5%) practice settings. For diagnostic lymphangiography, 100% (n = 48) performed intranodal pelvic lymphangiography. A 25-gauge needle was used by 77.1% (n = 37) to access pelvic lymph nodes, and most (83.3%; n = 40) reported using manual hand injection to administer ethiodized oil. Nine of 24 (37.5%) respondents in academic practice and 15 of 23 (65.2%) in private practice were successful in cannulating the thoracic duct >80% of the time. Most referrals were from thoracic surgery (n = 47; 97.9%). CONCLUSIONS: TDE is performed by practitioners in both academic and private practice settings. Treatment techniques were similar for a majority of operators. Technical success rates were higher in private practice. Most referrals were from thoracic surgery.

Single-Session Percutaneous Endovascular Mesocaval Shunt Creation and Balloon-Occluded Retrograde Transvenous Obliteration for the Treatment of Gastric Varices.

In the setting of portal hypertension, the body responds by creating portosystemic venous shunts, which may lead to the development of varices. Endoscopic treatment of these varices is often warranted to prevent catastrophic bleeding. During the course of variceal treatment, 1 or more portosystemic shunts may be sacrificed, which may acutely exacerbate portal hypertension and reduce systemic venous return. This report describes percutaneous creation of a mesocaval shunt and balloon-occluded retrograde transvenous obliteration (BRTO) in a patient with cavernous transformation of the portal vein. The patient had previously undergone an unsuccessful attempt at transjugular intrahepatic portosystemic shunt (TIPS) creation with postoperative bleeding requiring splenectomy. As TIPS was not feasible, creation of a percutaneous mesocaval shunt provided an alternate pathway for portosystemic decompression, facilitating safe treatment of gastric varices with BRTO via a gastrorenal shunt. These procedures were performed simultaneously to reduce the risk of variceal bleeding from acute changes in portal venous pressures and redirect blood flow through the shunt to maintain patency. This is the first reported case of combined mesocaval shunt placement and BRTO in a single session.

Pediatric lymphangiography, thoracic duct embolization and thoracic duct disruption: a single-institution experience in 11 children with chylothorax.

BACKGROUND: Interventional radiology treatment of chylothorax is well described in adults, with high technical and clinical success that decreases patient morbidity and mortality. However there is limited experience in children. OBJECTIVE: To report the technical and clinical success of lymphangiography, thoracic duct embolization and thoracic duct disruption in the pediatric population. MATERIALS AND METHODS: We studied 11 pediatric patients (7 boys, 4 girls; median weight 6.0 kg) who underwent lymphangiography and thoracic duct embolization from November 2015 to May 2017. All 11 (100%) children presented with chylothorax, with 1 (9%) having concomitant chylous ascites and 1 (9%) having concomitant chylopericardium. Ten (91%) children had traumatic chylothorax and one (9%) had congenital chylothorax. We recorded technical success, clinical success and complications. RESULTS: Twelve procedures were completed in 11 children. Bilateral intranodal lymphangiography was technically successful in all (100%) patients. Central lymphatics were visualized in eight (67%) procedures. Access to central lymphatics was attempted in eight procedures and successful in five (63%). In three (37%) of the eight procedures, disruption was performed when the central lymphatics could not be accessed. Clinical success was achieved in 7/11 (64%) children. Three minor complications were reported. No major complications were encountered. CONCLUSION: Lymphangiography, thoracic duct embolization and thoracic duct disruption are successful interventional strategies in children with chylothorax and should be considered as viable treatment options at any age.

Thoracic Duct Occlusion Leading to Intermittent Left Supraclavicular Swelling and Pancreatitis.

Intermittent left supraclavicular swelling is an uncommon and elusive condition that can lead to extensive diagnostic workups to determine the etiology and treatment. One potential cause is partial, intermittent, or complete thoracic duct occlusion (TDO). We report on a patient who presented with chronic, intermittent left supraclavicular swelling and abdominal pain that was relieved by thoracic duct angioplasty. Thoracic duct occlusion should be included in the differential diagnosis of left supraclavicular swelling. Lymphatic imaging can facilitate the diagnosis and allows for potential percutaneous treatment. Laryngoscope, 134:1313-1315, 2024.

Contemporary Use of Prophylactic Inferior Vena Cava Filters in Patients With Severe Traumatic Injuries and High Thromboembolic Event Risk.

PURPOSE: The aim of this study was to evaluate the relationship between prophylactic inferior vena cava filter (IVCF) implantation and in-hospital deep vein thrombosis (DVT), pulmonary embolism (PE), and mortality among adults with intracranial, pelvic or lower extremity, and spinal cord injuries. METHODS: Patients 18 years and older with severe intracranial, pelvic or lower extremity, or spinal cord injuries captured by the Trauma Quality Improvement Program (2010-2019) were identified. IVCFs implanted ≤72 hours after hospital presentation and before performance of lower extremity ultrasonography were defined as prophylactic. Patients were stratified by pharmacologic venous thromboembolism (VTE) prophylaxis status. Logistic regression models estimated prophylactic inferior vena cava (IVC) filtration's effect on selected outcomes and identified attributes associated with prophylactic IVCF implantation. RESULTS: Of 544,739 included patients, 1.3% (n = 7,247) underwent prophylactic IVCF implantation. Among patients who received pharmacologic VTE prophylaxis, prophylactic IVC filtration compared with expectant management was positively associated with DVT (odds ratio [OR], 4.30; P < .001) and PE (OR, 4.30; P < .001) but not associated with mortality (OR, 0.92; P = .43). Among patients who received no pharmacologic prophylaxis, prophylactic IVC filtration was positively associated with DVT (OR, 4.63; P < .001) and PE (OR, 5.02; P < .001) but negatively associated with mortality (OR, 0.43; P < .001). CONCLUSIONS: Prophylactic IVC filtration was associated with increased likelihood of VTE among all adults with severe intracranial, pelvic or lower extremity, and spinal cord injuries. In patients who received no pharmacologic VTE prophylaxis, prophylactic IVC filtration was associated with decreased likelihood of in-hospital mortality.

Collapse of inferior vena cava during complex filter retrieval with consequent intra-procedural systemic hypotension and bradycardia: a case report.

BACKGROUND: Prolonged dwelling time of inferior vena cava (IVC) filters has been shown to increase the need for the use of complex IVC filter retrieval techniques. In this report, we describe a case of complex retrieval of an IVC filter with prolonged dwelling time, which was temporarily accompanied by severe bradycardia and hypotension. CASE PRESENTATION: Fifty-nine-year-old male patient past medical history of morbid obesity, atrial fibrillation status post-ablation, obstructive sleep apnea, and end-stage renal disease presented for IVC filter retrieval 16 years after placement. When the IVC filter was covered by sheaths, and the IVC was temporarily collapsed and occluded, the patient developed severe bradycardia and hypotension without compensatory tachycardia. Contrast injection through the common femoral vein sheath showed complete occlusion of IVC while the IVC filter was covered by both sheaths, likely due to the embedment of the IVC filter in the wall by extensive fibrinous tissues. IVC filter was successfully retrieved, and the blood pressure and heart rate were improved immediately afterward. A large non-occlusive IVC thrombus was identified on the final venogram, which was aspirated using a mechanical thrombectomy device. CONCLUSION: Complex retrieval of IVC filters with prolonged dwelled time can result in acute severe bradycardia and hypotension due to vasovagal reaction, acute collapse, and occlusion of IVC in the setting of IVC filter embedment in the wall by extensive fibrinous tissues.

Percutaneous transhepatic cholangioscopy-guided lithotripsy and retrieval of vascular coils eroded into the biliary tree.

Endovascular coil erosion into the biliary system after hepatic artery embolization is a rare complication which may result in inflammation, strictures, choledocholithiasis, biliary colic, and cholangitis. Removal of coils may result in cessation of these symptoms, but is challenging in patients who cannot undergo removal via standard endoscopic approaches. This case report describes the retrieval of coils placed across a hepatic artery pseudoaneurysm, which over several years eroded into the biliary tree, resulting in calculi formation and post-prandial pain. Using combined fluoroscopy and cholangioscopy via percutaneous transhepatic accesses, the calculi were fragmented and the coils were retrieved, resulting in cessation of symptoms.

Characteristics of pivotal clinical trials of FDA-approved endovascular devices between 2000 and 2018: An interrupted time series analysis.

Background: The Food and Drug Administration (FDA) reviews safety, efficacy, and the quality of medical devices through its regulatory process. The FDA Safety and Innovation Act (FDASIA) of 2012 was aimed at accelerating the regulatory process for medical devices. Objectives: The purpose of our study was to (1) quantify characteristics of pivotal clinical trials (PCTs) supporting the premarket approval of endovascular medical devices and (2) analyze trends over the last two decades in light of the FDASIA. Methods: We surveyed the study designs of endovascular devices with PCTs from the US FDA pre-market approval medical devices database. The effect of FDASIA on key design parameters (e.g., randomization, masking, and number of enrolled patients) was estimated using an interrupted time series analysis (segmented regression). Results: We identified 117 devices between 2000-2018. FDASIA was associated with a decrease in double blinding (p < 0.0001) and a decrease in historical comparators (p < 0.0001). Discussion: Our results reveal an overall trend of decreased regulatory requirements as it relates to clinical trial characteristics, but a compensatory increased rate of post-approval across device classes. Furthermore, there was an emphasis on proving equivalence or non-inferiority rather than more use of active comparators in clinical trials. Medical device stakeholders, notably clinicians, must be aware of the shifting regulatory landscape in order to play an active role in promoting patient safety.

Use of Metformin and Survival in Patients with Hepatocellular Carcinoma (HCC) Undergoing Liver Directed Therapy: Analysis of a Nationwide Cancer Registry.

BACKGROUND: Examine the association of metformin use and overall survival (OS) in patients with HCC undergoing image-guided liver-directed therapy (LDT): ablation, transarterial chemoembolization (TACE), or Yttrium-90 radioembolization (Y90 RE). METHODS: Using National Cancer Institute Surveillance, Epidemiology, and End Results registry and Medicare claims databases between 2007 and 2016, we identified patients ≥ 66 years who underwent LDT within 30 days of HCC diagnosis. Patients with liver transplant, surgical resection, and other malignancies were excluded. Metformin use was identified by at least two prescription claims within 6 months before LDT. OS was measured by time between first LDT and death or last Medicare observation. Comparisons were performed between both all and diabetic patients on and not on metformin. RESULTS: Of 2746 Medicare beneficiaries with HCC undergoing LDT, 1315 (47.9%) had diabetes or diabetes-related complications. Among all and diabetic patients, 433(15.8%) and 402 (30.6%) were on metformin respectively. Median OS was greater for patients on metformin (19.6 months, 95% CI 17.1-23.0) vs those not (16.0 months, 15.0-16.9; p = 0.0238). Patients on metformin had lower risk of death undergoing ablation (HR 0.70; 0.51-0.95; p = 0.0239) and TACE (HR 0.76, 0.66-0.87; p = 0.0001), but not Y90 RE (HR1.22, 0.89-1.69; p = 0.2231). Among diabetics, OS was greater for those on metformin vs those not (HR 0.77, 0.68-0.88; p < 0.0001). Diabetic patients on metformin had longer OS undergoing TACE (HR 0.71, 0.61-0.83; p < 0.0001), but not ablation (HR 0.74, 0.52-1.04; p = 0.0886) or Y90 RE (HR 1.26, 0.87-1.85; p = 0.2217). CONCLUSION: Metformin use is associated with improved survival in HCC patients undergoing TACE and ablation.

Endovascular Treatment of Venous Outflow and Portal Venous Complications After Liver Transplantation.

Liver transplantation continues to rapidly evolve, and in 2020, 8906 orthotopic liver transplants were performed in the United States. As a technically complex surgery with multiple vascular anastomoses, stenosis and thrombosis of the venous anastomoses are among the recognized vascular complications. While rare, venous complications may be challenging to manage and can threaten the graft and the patient. In the last 20 years, endovascular approaches have been increasingly utilized to treat post-transplant venous complications. Herein, the evaluation and interventional treatment of post-transplant venous outflow complications, portal vein stenosis, portal vein thrombosis, and recurrent portal hypertension with transjugular intrahepatic portosystemic shunt (TIPS) are reviewed.

Correlation of Non-tumoral Liver Dose with Treatment-Related Adverse Events in Patients with Hepatocellular Carcinoma Treated with Glass-Based Yttrium-90 Radioembolization.

PURPOSE: To evaluate the relationship between non-tumor liver (NTL) dose and adverse events (AE) in patients with hepatocellular carcinoma (HCC) treated with glass-based Yttrium-90 radioembolization (Y90-RE). MATERIALS AND METHODS: A retrospective analysis of patients with HCC treated with Y90-RE between 2013 and 2018 was performed. Baseline characteristics including demographics and Y90-RE treatment approach were captured. Common Terminology Criteria for Adverse Events v5 was assessed at months 3 and 6 post-treatment. Using voxel-based dosimetry with MIM Software V. 6.9, dose-volume histograms of treated area of liver were created. Receiver operator characteristic curve was used to determine NTL dose threshold predicting AEs. Multivariate analysis was used to determine independent clinical factors of predicting severe AEs. Chi-square analysis was used to compare proportions. RESULTS: Two hundred and twenty-nine consecutive patients (115(50.2%) lobar and 114(49.8%) segmental) were included. At 3 months, there was a lower rate of any grade AE (55(46%) segmental and 36(31%) lobar, p = 0.009) and increased rate of severe AEs for lobar compared to segmental (2(2%) segmental and 9(8%) lobar, p = 0.029). At 6 months, severe AEs were greater for lobar than segmental (1(1%) segmental vs 10(9%) lobar, p = 0.005). For lobar Y90-RE, mean NTL dose of 112 Gy predicted severe AE (89% sensitivity and 91% specificity (AUC = 0.95, p = < 0.0001) at 3 and 6 months. For the segmental group, no significant association was found between NTL dose and severe treatment-related AE at 3 and 6 months. CONCLUSION: In patients with HCC undergoing glass-based lobar Y90-RE, NTL dose of > 112 Gy is associated with severe treatment-related AEs at 3-6 months.

ACR Appropriateness Criteria® Workup of Noncerebral Systemic Arterial Embolic Source.

Noncerebral systemic arterial embolism, which can originate from cardiac and noncardiac sources, is an important cause of patient morbidity and mortality. When an embolic source dislodges, the resulting embolus can occlude a variety of peripheral and visceral arteries causing ischemia. Characteristic locations for noncerebral arterial occlusion include the upper extremities, abdominal viscera, and lower extremities. Ischemia in these regions can progress to tissue infarction resulting in limb amputation, bowel resection, or nephrectomy. Determining the source of arterial embolism is essential in order to direct treatment decisions. This document reviews the appropriateness category of various imaging procedures available to determine the source of the arterial embolism. The variants included in this document are known arterial occlusion in the upper extremity, lower extremity, mesentery, kidneys, and multiorgan distribution that are suspected to be of embolic etiology. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.