Late Onset of Rivaroxaban-Associated Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis.

Although anti-thyroid drugs (ATDs) are the most common cause of drug-associated anti-neutrophil cytoplasmic antibody (ANCA) vasculitis (AAV), many other classes of drugs can lead to drug-associated AAV. We present a unique case of rivaroxaban-associated AAV. A 76-year-old female with a past medical history of atrial fibrillation on rivaroxaban presented with fatigue, bilateral lower extremity purpura, and hemoptysis to an outside hospital. Investigations revealed a positive cytoplasmic-ANCA (c-ANCA) titer of 1:320 and a positive anti-myeloperoxidase (anti-MPO), and negative perinuclear-ANCA (p-ANCA) and anti-proteinase 3 (anti-PR3). In addition, chest imaging demonstrated bilateral ground-glass opacities which raised suspicion for diffuse alveolar hemorrhage (DAH). A lung biopsy revealed acute and ongoing DAH with focally active capillaritis and characteristic pathological findings, which strongly suggested that was likely secondary to rivaroxaban. Rivaroxaban was discontinued, and the patient received pulses of intravenous glucocorticosteroids and rituximab. Her symptoms improved. She continued immunosuppressive therapy with rituximab for 2 years. She presented to our hospital for a second opinion regarding the discontinuation of rituximab, and we decided to discontinue rituximab. After discontinuation, the patient remained stable after 1.5 years of follow-up and did not have any relapses. This is a unique case of rivaroxaban-associated AAV. Clinicians should consider drug-associated AAV in all patients who present with an atypical clinical presentation and/or pathological findings of AAV. Given the broad and rapidly increasing use of novel anticoagulants, it is important to raise awareness of this potential complication. Prompt discontinuation of the drug and initiation of immunosuppressant treatment in severe cases may be lifesaving.

Incidentally Discovered Right Atrial Mass: A Rare and Unexpected Etiology.

Primary cardiac sarcoma is a rare type of intracardiac mass. This report describes a patient with atrial flutter who had a new right atrial mass incidentally discovered on transesophageal echocardiography. A thrombus was suspected based on radiographic appearance, but there was minimal change with anticoagulation. The mass was resected and found to be an undifferentiated pleomorphic cardiac sarcoma, an uncommon sub-type within the already rare category of primary cardiac neoplasms. This report highlights the importance of considering primary malignancy and thoroughly correlating radiographic and clinical evidence during the diagnostic workup of patients with intracardiac masses.

Dual Energy Technique Adds Value to Solitary Pulmonary Nodule Analysis with Dynamic Contrast-Enhanced CT: A 100 Nodule Experience.

A highly sensitive test for evaluation of solitary pulmonary nodules (SPN) involves a 5-phase, contrast enhanced CT evaluation which can be fraught with technical error. The goal of this study is to determine if qualitative evaluation of iodine maps with dual energy CT (DECT) can add value to SPN evaluation.100 patients had their SPN evaluated with traditional quantitative analysis and qualitative evaluation with iodine maps generated from DECT data acquired at 80 kVp and 140 kVp. Quantitative analysis served as the gold standard. Quantitative analysis was performed at 1, 2, 3, and 4 minutes. Qualitative Iodine maps analysis was performed at 1 and 2 minutes. Sensitivity and specificity were 63% and 95%, and 73% and 91%, respectively, at 1 and 2 minutes. Combined analysis resulted in sensitivity of 67% and specificity of 94%. Six of 7 false negatives on combined analysis were stable for 2 years and the seventh was lost to follow up after 1 year. Of 5 false positives on combined analysis; 2 were due to 'bleed-through of calcium' on iodine maps, 2 were positive on 3 and 4-minute quantitative analysis with one biopsy-proven adenocarcinoma. Qualitative analysis of Iodine maps generated using DECT data can be easily performed and may provide more effective evaluation of the solitary pulmonary nodule when combined with traditional analysis. This method warrants further investigation with larger patient populations, comparison with PET-CT, and evaluation of outcomes including long-term nodule stability and tissue diagnosis.

CT Fractional Flow Reserve: A Practical Guide to Application, Interpretation, and Problem Solving.

CT fractional flow reserve (FFRCT) is a physiologic simulation technique that models coronary flow from routine coronary CT angiography (CTA). To evaluate lesion-specific ischemia, FFRCT is measured 2 cm distal to a stenotic lesion. FFRCT greater than 0.8 is normal, 0.76-0.8 is borderline, and 0.75 or less is abnormal. FFRCT should always be interpreted in correlation with clinical and anatomic coronary CTA findings. FFRCT increases the specificity of coronary CTA in the evaluation of coronary artery disease, decreases the prevalence of nonobstructive disease in invasive coronary angiography (ICA), and helps with revascularization decisions and planning. Patients with intermediate-risk coronary anatomy at CTA and abnormal FFRCT can undergo ICA and revascularization, whereas those with normal FFRCT can be safely deferred from ICA. In borderline FFRCT values, management is decided in the context of the clinical scenario, but many cases could be safely managed with medical treatment. There are some limitations and pitfalls of FFRCT. Abnormal FFRCT values can be seen in mild stenosis, and normal FFRCTvalues can be seen in severe stenosis. Gradually decreasing or abnormal low FFRCT values at the distal vessel without a proximal focal lesion could be due to diffuse atherosclerosis. Coronary stents, bypass grafts, coronary anomalies, coronary dissection, transcatheter aortic valve replacement, unstable angina, and acute or recent myocardial infarction are situations in which FFRCT has not been validated and should not be used at this time. The authors provide a practical guide to the applications and interpretation of FFRCT, focusing on common pitfalls and challenges. Online supplemental material is available for this article. ©RSNA, 2022.

Unusual pneumoconiosis in two patients with heavy print toner, and paper dust exposure.

Workers in a print shop are exposed to photocopier toner dust and paper dust over a prolonged period of time. However, there are only rare case reports of toner and paper dust induced lung damage in humans. We reviewed our consultation files for a period of 30 years from 1987 to 2018 to look for cases with a diagnosis of giant cell interstitial pneumonia (GIP), printer toner exposure and paper dust exposure resulting in lung disease. There were two cases which met our inclusion criteria. Slides, clinical histories and imaging were reviewed. Both the patients had worked in print shops, and had no history of exposure to hard metals. Patient 1 presented with shortness of breath and cough over several months, while patient 2 was asymptomatic at presentation. Both the patients underwent surgical lung biopsies. Histopathologic examination from both the cases showed a spectrum of pathology, including features of GIP, desquamative interstitial pneumonia, chronic bronchiolitis with lymphoid hyperplasia, and particulate matter consistent with toner. Energy dispersive spectroscopy was performed on one case, and it revealed no cobalt or tungsten particles. The unusual combination of findings is very suggestive that toner particles with or without paper dust exposure were responsible for the pathologic changes in the lungs of these patients. This possibility should be explored further with additional patients who work in print shops where they are exposed to paper dust and paper toner and have signs or symptoms of diffuse lung disease.

An unusual variant of scimitar syndrome predisposing to recurrent pneumonia.

Scimitar syndrome is a rare constellation of congenital conditions pertaining to partial anomalous pulmonary venous return. Radiographically, these anomalous pulmonary veins can resemble a scimitar, and have heterogeneous clinical presentations. We present an unusual case of scimitar syndrome with associated recurrent pneumonia. We will briefly review the literature on scimitar syndrome as well as discuss how a predisposition to recurrent pneumonia may develop in this unusual variant of a rare clinical entity.

CT and MR Imaging of Cardiothoracic Vasculitis.

The term vasculitis includes a variable group of entities in which the common characteristic is inflammation of the walls of blood vessels occurring at some time during the course of the disease. The vasculitides can be divided into primary and secondary vasculitides, depending on the etiology and according to the size of the vessel affected. Both primary vasculitis and secondary vasculitis are associated with cardiac morbidity that is often subclinical. Cardiac involvement is associated with prognostic implications and higher rates of related mortality. Vasculitis of cardiac structures and the assessment of disease extent are important for appropriate management and selection of treatment. Although echocardiography, radionuclide imaging, and catheter-directed coronary angiography remain the cornerstones of cardiac imaging, cardiac computed tomography and magnetic resonance imaging can offer a 360° assessment of cardiac anatomy, function, and complications secondary to vasculitis. Postoperative complications, which are more frequent in patients with active disease, can also be depicted with those imaging modalities. A multidisciplinary approach is important to yield an appropriate estimate of the disease activity and extent and, therefore, to enable better treatment selection and monitoring. Online supplemental material is available for this article. ©RSNA, 2018.

Intrathoracic ganglioneuroma presenting as an endobronchial mass.

Peripheral nerve sheath tumors (PNST) are exceedingly rare, especially outside of the posterior mediastinum. These tumors represent less than 1% of pulmonary tumors. Very few pulmonary PNSTs are ganglioneuromas. We present a case of a ganglioneuroma presenting as an endobronchial mass. CASE PRESENTATION: An 80 year old male was seen in pulmonary clinic for routine cancer screening. He had a 60-pack year smoking history. CT evaluation noted a 1cm right lower lobe endobronchial lesion. This lesion was present since 2012 and had slightly increased in size since that time from 8mm (Figure 1). The lesion was further assessed using virtual bronchoscopy (Figure 2). Bronchoscopy revealed an obstructing lesion, which was completely excised with the snare (Figure 3). Pathology revealed well-circumscribed tumor consisting of nests and trabeculae of round/polygonal cells with granular eosinophilic and basophilic cytoplasm. The tumor was chromogranin, synaptophysin, S-100, pancytokeratin, SOX10, and TTF-1 positive, consistent with a ganglioneuroma. DISCUSSION: Aside from a solitary article regarding 75 patient samples (which included only one ganglioneuroma) only a small number of intrathoracic PNSTs have been reported. Only a single case report of an endobronchial ganglioneuroma has been reported. Each of these lesions were benign, and detected on routine imaging evaluations. CONCLUSIONS: An intrapulmonary endobronchial location for a PNST is an exceedingly rare presentation of an already uncommon pathology.

ACR Appropriateness Criteria® Known or Suspected Congenital Heart Disease in the Adult.

The incidence of congenital heart disease (CHD) has been increasing in the adult patient population in part as a result of better patient survival. Patients with more severe CHD are living longer. Nearly all adults with known CHD require periodic imaging as a means of monitoring their disease process. Furthermore, adult patients with suspected CHD require imaging as a means of definitive diagnosis. As a result, it is important for both the referring clinician and the imager to be aware of the most appropriate imaging modality needed to obtain the data most needed to direct the next steps in patient care. Imaging procedures for the diagnosis of known or suspected CHD in the adult include chest radiography, fluoroscopy, echocardiography, nuclear scintigraphy, cardiac-gated CT, MRI, and cardiac catheterization/angiography. The physician trying to diagnose these often complex conditions needs complete and reliable information that includes details about intracardiac and vascular anatomy, hemodynamics, and function. 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.

Cross-sectional Imaging Anatomy and Pathologic Conditions Affecting Thoracic Nerves.

While in many cases they are not directly visualized, awareness of the thoracic nerves and their courses at cross-sectional imaging is important for radiologists. An understanding of the normal function of each nerve is important, as many patients present with neurologic signs and symptoms that can be used to reinforce search patterns for disease and detection of supportive radiologic abnormalities. In the case of primary neoplasms, understanding the expected presence of a nerve in the location of a mass can enhance and improve the accuracy of differential diagnoses. Even in the absence of neurologic symptoms, secondary involvement of these structures by malignancy or close proximity to other intrathoracic disease can prompt significant alterations in oncologic or surgical management. The major components of the thoracic nervous system with which the thoracic radiologist must be familiar are the phrenic, vagus, recurrent laryngeal, intercostal, and long thoracic nerves in addition to the sympathetic chain and brachial plexus. The anatomic structure and course of each component are described including its major functions. Major clinical signs and symptoms attributable to nerve dysfunction or disease are reviewed as well as any associated radiologic signs. Emphasis is placed on primary and secondary malignant involvement of the nerves and iatrogenic and traumatic injuries. Online supplemental material is available for this article. ©RSNA, 2016.

Imaging of Pericardial Diseases.

Given the widespread use of cross-sectional imaging modalities, specifically multidetector computed tomography and magnetic resonance, to evaluate thoracic disease, the pericardium is frequently imaged. Knowledge of the normal appearance and anatomical boundaries is vital for radiologists to avoid confusion with more sinister pathology. A variety of disorders and diseases of the pericardium can bring a patient to clinical attention from inflammatory conditions, resulting in pericarditis and pericardial effusion, to malignancy. This article discusses the anatomy and conditions that affect the pericardium, emphasizing the role imaging plays in diagnosis and management.

Imaging in blunt cardiac injury: Computed tomographic findings in cardiac contusion and associated injuries.

BACKGROUND: Blunt cardiac injury (BCI) may manifest as cardiac contusion or, more rarely, as pericardial or myocardial rupture. Computed tomography (CT) is performed in the vast majority of blunt trauma patients, but the imaging features of cardiac contusion are not well described. PURPOSE: To evaluate CT findings and associated injuries in patients with clinically diagnosed BCI. MATERIALS AND METHODS: We identified 42 patients with blunt cardiac injury from our institution's electronic medical record. Clinical parameters, echocardiography results, and laboratory tests were recorded. Two blinded reviewers analyzed chest CTs performed in these patients for myocardial hypoenhancement and associated injuries. RESULTS: CT findings of severe thoracic trauma are commonly present in patients with severe BCI; 82% of patients with ECG, cardiac enzyme, and echocardiographic evidence of BCI had abnormalities of the heart or pericardium on CT; 73% had anterior rib fractures, and 64% had pulmonary contusions. Sternal fractures were only seen in 36% of such patients. However, myocardial hypoenhancement on CT is poorly sensitive for those patients with cardiac contusion: 0% of right ventricular contusions and 22% of left ventricular contusions seen on echocardiography were identified on CT. CONCLUSION: CT signs of severe thoracic trauma are frequently present in patients with severe BCI and should be regarded as indirect evidence of potential BCI. Direct CT findings of myocardial contusion, i.e. myocardial hypoenhancement, are poorly sensitive and should not be used as a screening tool. However, some left ventricular contusions can be seen on CT, and these patients could undergo echocardiography or cardiac MRI to evaluate for wall motion abnormalities.

ACR Appropriateness Criteria Acute Nonspecific Chest Pain-Low Probability of Coronary Artery Disease.

Primary imaging options in patients at low risk for coronary artery disease (CAD) who present with undifferentiated chest pain and without signs of ischemia are functional testing with exercise or pharmacologic stress-based electrocardiography, echocardiography, or myocardial perfusion imaging to exclude myocardial ischemia after rule-out of myocardial infarction and early cardiac CT because of its high negative predictive value to exclude CAD. Although possible, is not conclusive whether triple-rule-out CT (CAD, pulmonary embolism, and aortic dissection) might improve the efficiency of patient management. More advanced noninvasive tests such as cardiac MRI and invasive imaging with transesophageal echocardiography or coronary angiography are rarely indicated. With increased likelihood of noncardiac causes, a number of diagnostic tests, among them ultrasound of the abdomen, MR angiography of the aorta with or without contrast, x-ray rib views, x-ray barium swallow, and upper gastrointestinal series, can also be appropriate. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. This recommendation is based on excellent evidence, including several randomized comparative effectiveness trials and blinded observational cohort studies.

Pulmonary vascular diseases.

Pulmonary vascular diseases encompass a large and diverse group of underlying pathologies ranging from venous thromboembolism to congenital malformations to inflammatory vasculitides. As a result, patients can present either acutely with dyspnea and chest pain or chronically with dyspnea on exertion, hypoxia, and right heart failure. Imaging, particularly with multidetector CT, plays a key role in the evaluation and management of patients with suspected pulmonary vascular disease and, given the widespread routine use of high-quality CT pulmonary angiography, it is imperative that radiologists be familiar these pathologies.

ACR appropriateness criteria asymptomatic patient at risk for coronary artery disease.

Atherosclerotic cardiovascular disease is the leading cause of death for both men and women in the United States. Coronary artery disease has a long asymptomatic latent period and early targeted preventive measures can reduce mortality and morbidity. It is important to accurately classify individuals at elevated risk in order to identify those who might benefit from early intervention. Imaging advances have made it possible to detect subclinical coronary atherosclerosis. Coronary artery calcium score correlates closely with overall atherosclerotic burden and provides useful prognostic information for patient management. Our purpose is to discuss use of diagnostic imaging in asymptomatic patients at elevated risk for future cardiovascular events. The goal for these patients is to further refine targeted preventative efforts based on risk. The following imaging modalities are available for evaluating asymptomatic patients at elevated risk: radiography, fluoroscopy, multidetector CT, ultrasound, MRI, cardiac perfusion scintigraphy, echocardiography, and PET. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Computed tomography of blunt and penetrating diaphragmatic injury: sensitivity and inter-observer agreement of CT Signs.

Diaphragmatic injury is an uncommon but clinically important entity in the setting of trauma. Computed tomography (CT) is widely used to evaluate hemodynamically stable trauma patients. While prior studies have identified CT signs of diaphragm injury in blunt or penetrating trauma, no study has directly compared signs across these two types of injuries. We identified patients with surgically proven diaphragm injuries who underwent CT at presentation. Three reviewers examined each for 12 signs of diaphragm injury, as well as for an overall impression of diaphragm injury. We reviewed a total of 84 patients (37 % blunt trauma, 63 % penetrating). The initial interpreting radiologists discovered 77 % of blunt and 47 % of penetrating injuries (p = 0.01). We found that the majority of signs of diaphragmatic injury were split between those common in blunt trauma and those common in penetrating trauma, with minimal overlap. The presence of at least one blunt injury sign has 90 % sensitivity for diaphragm injury in blunt trauma; the presence of a wound tract traversing the diaphragm has 92 % sensitivity in penetrating trauma. Inter-observer reliability of these signs is also high (κ > 0.65). Penetrating diaphragm injuries present a different spectrum of imaging findings from those in blunt trauma and are underdiagnosed at CT; looking for a wound tract traversing the diaphragm is highly sensitive for diaphragm injury in these cases. Signs of organ or diaphragm fragment displacement are sensitive for blunt diaphragm injuries, consistent with these injuries being caused by increased intra-abdominal pressure.

ACR appropriateness criteria imaging for transcatheter aortic valve replacement.

Although aortic valve replacement is the definitive therapy for severe aortic stenosis, almost half of patients with severe aortic stenosis are unable to undergo conventional aortic valve replacement because of advanced age, comorbidities, or prohibitive surgical risk. Treatment options have been recently expanded with the introduction of catheter-based implantation of a bioprosthetic aortic valve, referred to as transcatheter aortic valve replacement. Because this procedure is characterized by lack of exposure of the operative field, image guidance plays a critical role in preprocedural planning. This guideline document evaluates several preintervention imaging examinations that focus on both imaging at the aortic valve plane and planning in the supravalvular aorta and iliofemoral system. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.