Crowdsourcing pneumothorax annotations using machine learning annotations on the NIH chest X-ray dataset.

Pneumothorax is a potentially life-threatening condition that requires prompt recognition and often urgent intervention. In the ICU setting, large numbers of chest radiographs are performed and must be interpreted on a daily basis which may delay diagnosis of this entity. Development of artificial intelligence (AI) techniques to detect pneumothorax could help expedite detection as well as localize and potentially quantify pneumothorax. Open image analysis competitions are useful in advancing state-of-the art AI algorithms but generally require large expert annotated datasets. We have annotated and adjudicated a large dataset of chest radiographs to be made public with the goal of sparking innovation in this space. Because of the cumbersome and time-consuming nature of image labeling, we explored the value of using AI models to generate annotations for review. Utilization of this machine learning annotation (MLA) technique appeared to expedite our annotation process with relatively high sensitivity at the expense of specificity. Further research is required to confirm and better characterize the value of MLAs. Our adjudicated dataset is now available for public consumption in the form of a challenge.

CT-based lung motion differences in patients with usual interstitial pneumonia and nonspecific interstitial pneumonia.

We applied quantitative CT image matching to assess the degree of motion in the idiopathic ILD such as usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP). Twenty-one normal subjects and 42 idiopathic ILD (31 UIP and 11 NSIP) patients were retrospectively included. Inspiratory and expiratory CT images, reviewed by two experienced radiologists, were used to compute displacement vectors at local lung regions matched by image registration. Normalized three-dimensional and two-dimensional (dorsal-basal) displacements were computed at a sub-acinar scale. Displacements, volume changes, and tissue fractions in the whole lung and the lobes were compared between normal, UIP, and NSIP subjects. The dorsal-basal displacement in lower lobes was smaller in UIP patients than in NSIP or normal subjects (p = 0.03, p = 0.04). UIP and NSIP were not differentiated by volume changes in the whole lung or upper and lower lobes (p = 0.53, p = 0.12, p = 0.97), whereas the lower lobe air volume change was smaller in both UIP and NSIP than normal subjects (p = 0.02, p = 0.001). Regional expiratory tissue fractions and displacements showed positive correlations in normal and UIP subjects but not in NSIP subjects. In summary, lung motionography quantified by image registration-based lower lobe dorsal-basal displacement may be used to assess the degree of motion, reflecting limited motion due to fibrosis in the ILD such as UIP and NSIP.

E-cigarette or vaping product use-associated lung injury: A review of clinico-radio-pathological characteristics.

Aggressive, albeit false marketing of electronic nicotine delivery systems (ENDS) or vaping devices as safer alternatives to cigarette smoking, combined with lack of regulations, has led to its mass adoption, especially among youth. A sudden increase in acute lung injuries was noted in 2019 which was linked to ENDS. It was termed by the Centers for Disease Control and Prevention (CDC) as electronic cigarette or vaping product use-associated lung injury (EVALI). Analysis of bronchoalveolar lavage fluid samples linked EVALI to vitamin E acetate (VEA), which is used as a diluting agent for marijuana oils. Patients with EVALI present with a combination of non-specific respiratory, gastrointestinal, and systemic symptoms. Laboratory results may show elevated inflammatory biomarkers. EVALI is a diagnosis of exclusion and must meet the following criteria: i) history of vaping within last 90 days, ii) abnormal chest imaging, iii) negative evaluation for infection, and iv) no other plausible diagnosis. A spectrum of computed tomography (CT) chest findings has been reported in EVALI, ranging from diffuse alveolar damage to organizing pneumonia, characterized by bilateral ground-glass opacities, consolidation, and septal thickening. A similar spectrum is seen on histopathology, characterized by lipid-laden alveolar macrophages, with varying degrees of infiltrative inflammatory cells and fibrin deposition. Early and accurate identification of the EVALI pattern can help optimize patient care. For example, in diffuse alveolar damage (DAD), a lower threshold for ventilation support and corticosteroid may improve outcomes. Here, we review the etiopathogenesis, clinical management, histopathology, and imaging features of EVALI.

ACR Appropriateness Criteria® Chronic Cough.

Chronic cough is defined by a duration lasting at least 8 weeks. The most common causes of chronic cough include smoking-related lung disease, upper airway cough syndrome, asthma, gastroesophageal reflux disease, and nonasthmatic eosinophilic bronchitis. The etiology of chronic cough in some patients may be difficult to localize to an isolated source and is often multifactorial. The complex pathophysiology, clinical presentation, and variable manifestations of chronic cough underscore the challenges faced by clinicians in the evaluation and management of these patients. Imaging plays a role in the initial evaluation, although there is a lack of high-quality evidence guiding which modalities are useful and at what point in time the clinical evaluation should be performed. 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.

ACR Appropriateness Criteria® Intensive Care Unit Patients.

Chest radiography is the most frequent and primary imaging modality in the intensive care unit (ICU), given its portability, rapid image acquisition, and availability of immediate information on the bedside preview. Due to the severity of underlying disease and frequent need of placement of monitoring devices, ICU patients are very likely to develop complications related to underlying disease process and interventions. Portable chest radiography in the ICU is an essential tool to monitor the disease process and the complications from interventions; however, it is subject to overuse especially in stable patients. Restricting the use of chest radiographs in the ICU to only when indicated has not been shown to cause harm. The emerging role of bedside point-of-care lung ultrasound performed by the clinicians is noted in the recent literature. The bedside lung ultrasound appears promising but needs cautious evaluation in the future to determine its role in ICU patients. 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.

Relative Regional Air Volume Change Maps at the Acinar Scale Reflect Variable Ventilation in Low Lung Attenuation of COPD patients.

OBJECTIVES: The purpose of this study was to investigate regional air volume changes at the acinar scale of the lung in chronic obstructive pulmonary disease (COPD) patients using an image registration technique. MATERIALS AND METHODS: Thirty-four emphysema patients and 24 subjects with normal chest CT and pulmonary function test (PFT) results were included in this retrospective study for which informed consent was waived by the institutional review board. After lung segmentation, a mass-preserving image registration technique was used to compute relative regional air volume changes (RRAVCs) between inspiration and expiration CT scans. After determining the appropriate thresholds of RRAVCs for low ventilation areas (LVAs), they were displayed and analyzed using color maps on the background inspiration CT image, and compared with the low attenuation area (LAA) map. Correlations between quantitative CT parameters and PFTs were assessed using Pearson's correlation test, and parameters were compared between emphysema and normal-CT patients using the Student's t-test. RESULTS: LVA percentage with an RRAVC threshold of 0.5 (%LVA0.5) showed the strongest correlations with FEV1/FVC (r = -0.566), FEV1 (r = -0.534), %LAA-950insp (r = 0.712), and %LAA-856exp (r = 0.775). %LVA0.5 was significantly higher (P < 0.001) in COPD patients than normal subjects. Despite the identical appearance of emphysematous lesions on the LAA-950insp map, the RRAVC map depicted a wide range of ventilation differences between these LAA clusters. CONCLUSION: RRAVC-based %LVA0.5 correlated well with FEV1/FVC, FEV1, %LAA-950insp and %LAA-856exp. RRAVC holds the potential for providing additional acinar scale functional information for emphysematous LAAs in inspiratory CT images, providing the basis for a novel set for emphysematous phenotypes.

ACR Appropriateness Criteria® Hemoptysis.

Hemoptysis, the expectoration of blood, ranges in severity from nonmassive to massive. This publication reviews the literature on the imaging and treatment of hemoptysis. Based on the literature, the imaging recommendations for massive hemoptysis are both a chest radiograph and CT with contrast or CTA with contrast. Bronchial artery embolization is also recommended in the majority of cases. In nonmassive hemoptysis, both a chest radiograph and CT with contrast or CTA with contrast is recommended. Bronchial artery embolization is becoming more commonly utilized, typically in the setting of failed medical therapy. Recurrent hemoptysis, defined as hemoptysis that recurs following initially successful cessation of hemoptysis, is best reassessed with a chest radiograph and either CT with contrast or CTA with contrast. Bronchial artery embolization is increasingly becoming the treatment of choice in recurrent hemoptysis, with the exception of infectious causes such as in cystic fibrosis. 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.

Low-dose sirolimus in retroperitoneal lymphangioleiomyomas.

Lymphangioleiomyomatosis (LAM) is a rare disease associated with cystic lung destruction and abdominal tumors, including lymphangioleiomyomas, which frequently occur in the retroperitoneal region. Sirolimus therapy is currently recommended for LAM patients with abnormal or declining lung function with an adjusted dose to maintain a serum trough level of 5-15 ng/mL. We describe a significant reduction of retroperitoneal lymphangioleiomyomas after treatment with low-dose sirolimus therapy (serum trough level <5 ng/mL) in a patient with sporadic LAM.

Augmenting the National Institutes of Health Chest Radiograph Dataset with Expert Annotations of Possible Pneumonia.

This dataset is intended to be used for machine learning and is composed of annotations with bounding boxes for pulmonary opacity on chest radiographs which may represent pneumonia in the appropriate clinical setting.

ACR Appropriateness Criteria® Rib Fractures.

Rib fractures are the most common thoracic injury after minor blunt trauma. Although rib fractures can produce significant morbidity, the diagnosis of injuries to underlying organs is arguably more important as these complications are likely to have the most significant clinical impact. Isolated rib fractures have a relatively low morbidity and mortality and treatment is generally conservative. As such, evaluation with standard chest radiographs is usually sufficient for the diagnosis of rib fractures, and further imaging is generally not appropriate as there is little data that undiagnosed isolated rib fractures after minor blunt trauma affect management or outcomes. Cardiopulmonary resuscitation frequently results in anterior rib fractures and chest radiographs are usually appropriate (and sufficient) as the initial imaging modality in these patients. In patients with suspected pathologic fractures, chest CT or Tc-99m bone scans are usually appropriate and complementary modalities to chest radiography based on the clinical scenario. 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.

ACR Appropriateness Criteria® Lung Cancer Screening.

Lung cancer remains the leading cause of cancer death in both men and women. Smoking is the single greatest risk factor for the development of lung cancer. For patients between the age of 55 and 80 with 30 or more pack years smoking history who currently smoke or who have quit within the last 15 years should undergo lung cancer screening with low-dose CT. In patients who do not meet these criteria but who have additional risk factors for lung cancer, lung cancer screening with low-dose CT is controversial but may be appropriate. Imaging is not recommended for lung cancer screening of patient younger than 50 years of age or patients older than 80 years of age or patients of any age with less than 20 packs per year history of smoking and no additional risk factor (ie, radon exposure, occupational exposure, cancer history, family history of lung cancer, history of COPD, or history of pulmonary fibrosis). 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.

ACR Appropriateness Criteria® Dyspnea-Suspected Cardiac Origin.

This article discusses imaging guidelines for five dyspnea variants: (1) dyspnea due to heart failure, ischemia not excluded; (2) dyspnea due to suspected nonischemic heart failure, ischemia excluded; (3) dyspnea due to suspected valvular heart disease, ischemia excluded; (4) dyspnea due to suspected cardiac arrhythmia, ischemia excluded; and (5) dyspnea due to suspected pericardial disease, ischemia excluded. 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.

The Influence of a Vocalized Checklist on Detection of Multiple Abnormalities in Chest Radiography.

RATIONALE AND OBJECTIVES: Although a checklist has been recommended for preventing satisfaction of search (SOS) errors, a previous research study did not demonstrate that benefit. However, observers in that study had to turn away from the image display to use the checklist. The current study tested a vocalized checklist to avoid this constraint. MATERIALS AND METHODS: A total of 64 chest computed radiographs, half containing various "test" abnormalities, were read twice by 20 radiologists, once with and once without the addition of a simulated pulmonary nodule. Readers used a vocalized checklist-directing search. Receiver operating characteristic (ROC) detection accuracy and decision thresholds were analyzed to study the effects of adding the nodule on detecting the test abnormalities. RESULTS: Adding nodules induced a substantial reluctance to report the other abnormalities (P < 0.001), as had been the case in the most recent study of the SOS effect in radiography. CONCLUSIONS: The vocalized checklist did not reduce nor eliminate the SOS effect on readiness to report further abnormalities. Although useful for organizing search and reporting, particularly among students, a vocalized checklist does not prevent SOS effects.

What's New in 10 Years? A Revised Cardiothoracic Curriculum for Diagnostic Radiology Residency with Goals and Objectives Related to General Competencies.

This is a cardiothoracic curriculum document for radiology residents meant to serve not only as a study guide for radiology residents but also as a teaching and curriculum reference for radiology educators and radiology residency program directors. This document represents a revision of a cardiothoracic radiology resident curriculum that was published 10 years ago in Academic Radiology. The sections that have been significantly revised, expanded, or added are (1) lung cancer screening, (2) lung cancer genomic profiling, (3) lung adenocarcinoma revised nomenclature, (4) lung biopsy technique, (5) nonvascular thoracic magnetic resonance, (6) updates to the idiopathic interstitial pneumonias, (7) cardiac computed tomography updates, (8) cardiac magnetic resonance updates, and (9) new and emerging techniques in cardiothoracic imaging. This curriculum was written and endorsed by the Education Committee of the Society of Thoracic Radiology. This curriculum operates in conjunction with the Accreditation Council for Graduate Medical Education (ACGME) milestones project that serves as a framework for semiannual evaluation of resident physicians as they progress through their training in an ACGME-accredited residency or fellowship programs. This cardiothoracic curriculum document is meant to serve not only as a more detailed guide for radiology trainees, educators, and program directors but also complementary to and guided by the ACGME milestones.

Beyond warfarin: The advent of new oral anticoagulants.

New oral anticoagulants (NOAC) are the latest addition to anticoagulant armamentarium. Unlike traditional anti-coagulants like warfarin, lab monitoring and management of bleeding complications secondary to these agents is different. As more and more patients are being switched to these drugs, interventional radiologists in particular will benefit from a clinical review of NOAC.

Catheter-based transarterial therapies for hepatocellular cancer.

As the prevalence of liver cancer increases, so does the demand for nonsurgical, minimally invasive alternatives to surgery, since many patients have tumors that cannot be surgically resected. Catheter-based hepatic arterial procedures may be an option in patients with primary and metastatic liver cancer. The authors describe four catheter-based hepatic arterial procedures and outline the management of potential complications during the immediate postprocedural period.

Satisfaction of Search in Chest Radiography 2015.

RATIONALE AND OBJECTIVES: Two decades have passed since the publication of laboratory studies of satisfaction of search (SOS) in chest radiography. Those studies were performed using film. The current investigation tests for SOS effects in computed radiography of the chest. METHODS: Sixty-four chest computed radiographs half demonstrating various "test" abnormalities were read twice by 20 radiologists, once with and once without the addition of a simulated pulmonary nodule. Receiver-operating characteristic detection accuracy and decision thresholds were analyzed to study the effects of adding the nodule on detecting the test abnormalities. Results of previous studies were reanalyzed using similar modern techniques. RESULTS: In the present study, adding nodules did not influence detection accuracy for the other abnormalities (P = .93), but did induce a reluctance to report them (P < .001). Adding nodules did not affect inspection time (P = .58) so the reluctance to report was not associated with reduced search. Reanalysis revealed a similar decision threshold shift that had not been recognized in the early studies of SOS in chest radiography (P < .01) in addition to reduced detection accuracy (P < .01). CONCLUSIONS: The nature of SOS in chest radiography has changed, but it is not clear why. ADVANCES IN KNOWLEDGE: SOS may be changing as a function of changes in radiology education and practice.

Endothelium and the lipid metabolism: the current understanding.

The endothelium is a dynamic organ and responds to various physical and humoral conditions. The endothelium secretes several biologically active substances, both vasoconstrictors and vasodilators, which control these processes. Endothelial function is most commonly assessed as the vasodilatory response to stimuli. Several endothelium-dependent agonists have been identified, each of which acts through a membrane receptor. Nitric oxide which is continuously synthesized by the endothelium has a wide range of biological properties that maintain vascular homeostasis. It is a potent vasodilator and inhibitor of platelet aggregation and thus has an important protective role. Endothelial dysfunction in hypercholesterolemic patients is in large part due to a reduced bioavailability of NO. Traditional coronary risk factors, especially hypercholesterolemia, produce endothelial dysfunction even in patients with normal blood vessels. The underlying mechanisms involve a local inflammatory response, release of cytokines and growth factors, activation of oxidation-sensitive mechanisms in the arterial wall, modulation of intracellular signaling pathways, increased oxidation of low-density lipoprotein cholesterol, and quenching of nitric oxide. Clinical studies have shown a significant improvement in endothelial dysfunction following lowering of serum cholesterol levels, infusion of nitric oxide donors like L-arginine and exercise training. Clinical trials are underway examining the role of endothelin-1 receptor antagonists like bosentan in the prevention of graft atherosclerosis.

Drug-eluting stents. A review of the current literature.

Coronary interventions have revolutionized the treatment of coronary artery disease (CAD). Stents, which were used initially for the complications arising from coronary angiography gradually, came to occupy a more prominent role in coronary interventions. However, restenosis remained a limiting factor from a therapeutic point of view. Recent development of drug-eluting stents is a step toward overcoming this problem. This development has elicited a great interest in both physician as well as patient communities. We have reviewed the available medical evidence regarding drug-eluting stents.