ACR Appropriateness Criteria® Dialysis Fistula Malfunction.

The creation and maintenance of a dialysis access is vital for the reduction of morbidity, mortality, and cost of treatment for end stage renal disease patients. One's longevity on dialysis is directly dependent upon the quality of dialysis. This quality hinges on the integrity and reliability of the access to the patient's vascular system. All methods of dialysis access will eventually result in dialysis dysfunction and failure. Arteriovenous access dysfunction includes 3 distinct classes of events, namely thrombotic flow-related complications or dysfunction, nonthrombotic flow-related complications or dysfunction, and infectious complications. The restoration of any form of arteriovenous access dysfunction may be supported by diagnostic imaging, clinical consultation, percutaneous interventional procedures, surgical management, or a combination of these methods. This document provides a rigorous evaluation of how variants of each form of dysfunction may be appraised and approached systematically. 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 process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Management of Liver Cancer: 2022 Update.

The treatment and management of hepatic malignancies can be complex because it encompasses a variety of primary and metastatic malignancies and an assortment of local and systemic treatment options. When to use each of these treatments is critical to ensure the most appropriate care for patients. Interventional radiologists have a key role to play in the delivery of a variety of liver directed treatments including percutaneous ablation, transarterial embolization with bland embolic particles alone, transarterial chemoembolization (TACE) with injection of a chemotherapeutic emulsion, and transarterial radioembolization (TARE). Based on 9 clinical variants, the appropriateness of each treatment is described in this document. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Extrinsic compression of coronary and pulmonary vasculature.

Coronary artery disease from atherosclerosis induced stenosis remains the leading cause of acute coronary syndrome (ACS) and death worldwide, however extrinsic compression of coronary arteries from adjacent anatomical and pathological structures is an infrequent but important diagnosis to be aware of, especially given the nonspecific symptoms of chest pain that mimic angina in patients with pulmonary hypertension (PHT) and congenital heart disease. Non-invasive CT angiography is an invaluable diagnostic tool for detection of coronary artery compression, pulmonary artery dilatation and pulmonary vascular compression. Although established guidelines are not available for management of left main coronary artery (LMCA) compression syndrome, percutaneous coronary intervention and stent implantation remain a feasible option for the treatment, specifically for patients with a high surgical risk. Treatment of pulmonary vein or artery compression is more varied and determined by etiology. This review article is focused on detailed discussion of extrinsic compression of coronary arteries, mainly the LMCA and brief discussion on pulmonary vasculature compression by surrounding anatomical and pathological entities, with focus on pathophysiology, clinical features, complications and role of imaging in its diagnosis and management.

ACR-ABS-ACNM-ASTRO-SIR-SNMMI practice parameter for selective internal radiation therapy or radioembolization for treatment of liver malignancies.

PURPOSE: The American College of Radiology (ACR), American Brachytherapy Society (ABS), American College of Nuclear Medicine (ACNM), American Society for Radiation Oncology (ASTRO), Society of Interventional Radiology (SIR), and Society of Nuclear Medicine and Molecular Imaging (SNMMI) have jointly developed a practice parameter on selective internal radiation therapy (SIRT) or radioembolization for treatment of liver malignancies. Radioembolization is the embolization of the hepatic arterial supply of hepatic primary tumors or metastases with a microsphere yttrium-90 brachytherapy device. MATERIALS AND METHODS: The ACR -ABS -ACNM -ASTRO -SIR -SNMMI practice parameter for SIRT or radioembolization for treatment of liver malignancies was revised in accordance with the process described on the ACR website (https://www.acr.org/ClinicalResources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters-Interventional and Cardiovascular Radiology of the ACR Commission on Interventional and Cardiovascular, Committee on Practice Parameters and Technical Standards-Nuclear Medicine and Molecular Imaging of the ACR Commission on Nuclear Medicine and Molecular Imaging and the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with ABS, ACNM, ASTRO, SIR, and SNMMI. RESULTS: This practice parameter is developed to serve as a tool in the appropriate application of radioembolization in the care of patients with conditions where indicated. It addresses clinical implementation of radioembolization including personnel qualifications, quality assurance standards, indications, and suggested documentation. CONCLUSIONS: This practice parameter is a tool to guide clinical use of radioembolization. It focuses on the best practices and principles to consider when using radioemboliozation effectively. The clinical benefit and medical necessity of the treatment should be tailored to each individual patient.

Retrospective Comparison of Pulmonary Arteriovenous Malformation Embolization with the Polytetrafluoroethylene-Covered Nitinol Microvascular Plug, AMPLATZER Plug, and Coils in Patients with Hereditary Hemorrhagic Telangiectasia.

PURPOSE: To evaluate effectiveness of the polytetrafluoroethylene-covered nitinol mesh microvascular plug (MVP) and compare it with other devices in pulmonary arteriovenous malformation (PAVM) embolization in patients with hereditary hemorrhagic telangiectasia (HHT). MATERIALS AND METHODS: Twenty-five patients (average age 35 y; range, 15-56 y) with hereditary hemorrhagic telangiectasia (HHT) and de novo PAVM embolization with at least 1 MVP between November 2015 and May 2017 were retrospectively evaluated. Retrospective data were also obtained from prior embolization procedures in the same patient population with other embolic devices dating back to 2008. Technical success, complications, PAVM persistence rates, and category of persistence were analyzed. RESULTS: In 25 patients, 157 PAVMs were treated: 92 with MVP, 35 with AMPLATZER vascular plug (AVP), 6 with AVP plus coils, and 24 with coils. The per-PAVM technical success rates were 100% with MVP; 97%, AVP; 100%, AVP plus coils; and 100%, coils. PAVM persistence rates and median follow-up were as follows: MVP, 2% (1/92) (510 d); AVP, 15% (3/20) (1,447 d); AVP plus coils, 20% (1/5) (1,141 d); coils, 46.7% (7/15) (1,141 d). Persistence owing to recanalization for MVP, AVP, AVP plus coils, and coils was 2%, 15%, 0%, and 33%. No difference was found between persistence rates of MVP vs AVP (P = .098). Embolization with a vascular plug (MVP or AVP) with or without coils had a statistically significant lower persistence rate (5.4%) than embolization with coils alone (46.7%) (P = .022). CONCLUSIONS: PAVM embolization with MVP had a high technical success rate and a low persistence rate comparable to AVP and lower than coil embolization alone.

Pulmonary vascular anatomy & anatomical variants.

The vessels supplying the lungs include the pulmonary arteries, pulmonary veins, and bronchial arteries. The segmental and sub segmental pulmonary arteries parallel the bronchi and are named according to the bronchopulmonary segments they supply. There are however considerable anatomic variations, particularly in the upper lobes with variations in number or presence of accessory arteries from adjacent segments. The subsegmental pulmonary vein branches, run within interlobular septa and do not parallel the segmental or sub segmental pulmonary artery branches and bronchi. They converge to form right and left superior and inferior pulmonary veins which drain into the left atrium. Knowledge of normal and variant anatomy on cross-sectional and angiographic images is essential for accurate diagnosis of vascular pathology and aids planning of interventional procedures.

Pulmonary vascular pathophysiology.

Knowledge of pulmonary vascular pathophysiology is crucial to understand the various disease processes and their medical management. Pulmonary vascular system constitutes the right sided circulation which is distinct from the left side circulation and facilitates unique hemodynamic properties to adapt to a multitude of external demands and circumstances. With growing prevalence and increasing ability to diagnose and treat pulmonary diseases, this review becomes more relevant.

Imaging of acute pulmonary embolism: an update.

Imaging plays an important role in the evaluation and management of acute pulmonary embolism (PE). Computed tomography (CT) pulmonary angiography (CTPA) is the current standard of care and provides accurate diagnosis with rapid turnaround time. CT also provides information on other potential causes of acute chest pain. With dual-energy CT, lung perfusion abnormalities can also be detected and quantified. Chest radiograph has limited utility, occasionally showing findings of PE or infarction, but is useful in evaluating other potential causes of chest pain. Ventilation-perfusion (VQ) scan demonstrates ventilation-perfusion mismatches in these patients, with several classification schemes, typically ranging from normal to high. Magnetic resonance imaging (MRI) also provides accurate diagnosis, but is available in only specialized centers and requires higher levels of expertise. Catheter pulmonary angiography is no longer used for diagnosis and is used only for interventional management. Echocardiography is used for risk stratification of these patients. In this article, we review the role of imaging in the evaluation of acute PE.

Pulmonary vasculitis: diagnosis and endovascular therapy.

Pulmonary vasculitides are caused by a heterogeneous group of diseases with different clinical features and etiologies. Radiologic manifestations depend on the predominant type of vessel involved, which are grouped into large, medium, or small-sized vessels. Diagnosing pulmonary vasculitides is a challenging task, and radiologists play an important role in their management by providing supportive evidence for diagnosis and opportunities for minimally invasive therapy. This paper aims to present a practical approach for understanding the vasculitides that can affect the pulmonary vessels and lungs. We will describe and illustrate the main radiologic findings, discussing opportunities for minimally invasive treatment.

Pulmonary arteriovenous malformations: diagnosis.

Pulmonary arteriovenous malformations (PAVMs) are rare, abnormal low resistance vascular structures that connect a pulmonary artery to a pulmonary vein, thereby bypassing the normal pulmonary capillary bed and resulting in an intrapulmonary right-to-left shunt. The spectrum of PAVMs extends from microscopic lesions causing profound hypoxemia and ground glass appearance on computed tomography (CT) but with normal catheter angiographic findings to classic pulmonary aneurysmal connections that abnormally connect pulmonary veins and arteries. These malformations most commonly are seen in hereditary hemorrhagic telangiectasia (HHT). They are rarely due to secondary conditions such as post congenital heart disease surgery or hepatopulmonary syndrome (HPS). The main complications of PAVM result from intrapulmonary shunt and include stroke, brain abscess, and hypoxemia. Local pulmonary complications include PAVM rupture leading to life-threatening hemoptysis or hemothorax. The preferred screening test for PAVM is transthoracic contrast echocardiography (TTCE). CT has become the gold standard imaging test to establish the presence of PAVM. Endovascular occlusion of the feeding artery is the treatment of choice. Collateralization and recanalization of PAVM following treatment may occur, and hence long term clinical and imaging follow-up is required to assess PAVM enlargement and PAVM reperfusion.

Pulmonary arteriovenous malformations: endovascular therapy.

Pulmonary arteriovenous malformations (PAVM) are abnormal direct communications between the branches of pulmonary arteries and veins, and are often seen in patients with hereditary hemorrhagic telangiectasia (HHT). If untreated, the right to left shunt can result in symptoms of hypoxemia, paradoxical emboli to the left side circulation, stroke and intracranial abscess. Endovascular therapy is a minimally invasive outpatient based treatment wherein the feeding artery to the PAVM is occluded with coils or plugs or a combination of both and is associated with minimal morbidity and no mortality. In this manuscript, we will review the indications and contraindications for endovascular therapy, pre-procedural work up, procedure technique and variations, complications, and outcomes.

Pulmonary artery aneurysms: diagnosis & endovascular therapy.

Pulmonary artery aneurysms (PAAs) and pseudoaneurysms are rare entities in the spectrum of pulmonary arterial diseases. The etiology of these aneurysms is varied and patients present with nonspecific symptoms which make their diagnosis both difficult and less often considered. In this review, we will discuss the clinical manifestations, etiologies, methods of detection, imaging features, and the current role of endovascular treatment in the management of PAAs.

Diagnosis and interventions of vascular complications in lung transplant.

Though rare, pulmonary vascular complications after lung transplantation carry high morbidity and mortality. Knowledge of the normal and abnormal appearance of lung transplant vasculature is essential for timely and appropriate diagnosis and management of complications. Appropriate selection of surgical and endovascular treatments depend on the availability of expertise and requires a multidisciplinary approach to ensure the best outcomes.

Pain After Percutaneous Irreversible Electroporation of Renal Tumors Is Not Dependent on Tumor Location.

INTRODUCTION: Irreversible electroporation (IRE) is a non-thermal minimally invasive technique that is used to treat small renal masses (SRMs). Prior work has demonstrated greater narcotic requirements after radiofrequency ablation (RFA) for tumors that are closer to body-wall musculature. We hypothesized that pain after IRE is not dependent on tumor location due to the athermal mechanistic action. MATERIALS AND METHODS: A retrospective review of 50 consecutive percutaneous IRE and RFA cases was performed from 2013 to 2014. Eight patients were excluded from analysis due to incomplete anesthesia record and/or multiple ablations per session, leaving 21 patients in each group. Data collected included patient age, sex, body mass index, nephrometry score, shortest distance to the closest body-wall muscle, perioperative narcotic use, and patient-reported pain score. Pearson correlation test and multivariable linear regression were used to identify predictors of postoperative pain, with significance set at p = 0.05. RESULTS: There was no difference in the mean distance from tumor edge to the nearest body-wall muscle between IRE and RFA (2.6 cm vs 2.4 cm, p = 0.729, respectively). Total mean perioperative narcotic usage was 20.4 mg after IRE and 26.7 mg after RFA (p = 0.096). Mean postoperative pain score (scale 0-10) was slightly higher after RFA (4.3) compared with IRE (2.4), but this was not statistically significant (p = 0.088). Pearson correlation test identified tumor proximity to be significiantly associated with both pain score (p = 0.011) and postoperative narcotic use (p = 0.049) after RFA but not after IRE. On multivariable analysis, only tumor proximity to the body wall was significantly correlated to pain score (-1.4, p = 0.041) after RFA but was not found to be a factor for pain after IRE. CONCLUSIONS: Patients whose tumors lie close to their body-wall musculature do not have greater narcotic requirements or higher pain scores in the perioperative period after IRE. Percutaneous IRE may be preferred over RFA for SRMs that are close to the body wall to minimize pain.

How I do it: percutaneous radiofrequency ablation (RFA).

Percutaneous radiofrequency ablation has seen increased utilization secondary to the rising incidence of renal cell carcinoma. This has been shown to be an effective and durable treatment especially in the elderly comorbid patient. In this article, we describe our technique and factors related to successful outcomes.

Interventional radiology in the management of thoracic duct injuries: Anatomy, techniques and results.

Disruption of the thoracic duct can have devastating consequences and be associated with a high morbidity and mortality. Conservative therapies have been attempted to treat chylothorax without much success. Surgical management has traditionally been necessary to provide definitive treatment at the expense of increased morbidity. Lymphatic interventions have recently emerged as a new frontier for interventional radiologists to add value and provide minimally invasive therapies for debilitating conditions. The goal of this manuscript is to review the anatomy of the thoracic duct, describe various percutaneous techniques for accessing the duct, and briefly discuss outcomes as reported in the literature.

Thrombolysis and Transjugular Intrahepatic Portosystemic Shunt Creation for Acute and Subacute Portal Vein Thrombosis.

Catheter-based interventional therapy offers a safe and effective option for treatment of symptomatic portomesenteric venous thrombosis refractory to medical therapy. Various techniques and approaches have been described for thrombolysis and thrombectomy and re-establishing the portal venous flow for select populations. Early diagnosis and prompt treatment based on clinical presentation, imaging, and underlying anatomy are necessary to prevent long-term complications. This article describes various catheter-based approaches for treatment of acute and subacute portal vein thrombosis.

Complications of inferior vena cava filters.

Inferior vena cava (IVC) filter placement is a relatively low risk alternative for prophylaxis against pulmonary embolism in patients with pelvic or lower extremity deep venous thrombosis who are not suitable for anticoagulation. There is an increasing trend in the number of IVC filter implantation procedures performed every year. There are many device types in the market and in the early 2000s, the introduction of retrievable filters brought an additional subset of complications to consider. Modern filter designs have led to decreased morbidity and mortality, however, a thorough understanding of the limitations and complications of IVC filters is necessary to weight the risks and benefits of placing IVC filters. In this review, the complications associated with IVC filters are divided into procedure related, post-procedure, and retrieval complications. Differences amongst the device types and retrievable filters are described, though this is limited by a significant lack of prospective studies. Additionally, the clinical presentation as well as prevention and treatment strategies are outlined with each complication type.

Image-guided percutaneous ablation of lung malignancies: A minimally invasive alternative for nonsurgical patients or unresectable tumors.

Lung cancer remains the malignancy with the highest mortality and second highest incidence in both men and women within the United States. Image-guided ablative therapies are safe and effective for localized control of unresectable liver, renal, bone, and lung tumors. Local ablative therapies have been shown to slow disease progression and prolong disease-free survival in patients who are not surgical candidates, either due to local extent of disease or medical comorbidities. Commonly encountered complications of percutaneous ablation of lung tumors include pneumothorax, pleural inflammation, pleural effusions, and pneumonia, which are usually easily managed. This review will discuss the merits of image-guided ablation in the treatment of lung tumors and the underlying mechanism, procedural techniques, clinical utility, toxicity, imaging of tumor response, and future developments, with a focus on radiofrequency ablation.