Persistent mucus plugs in proximal airways are consequential for airflow limitation in asthma.

BACKGROUNDInformation about the size, airway location, and longitudinal behavior of mucus plugs in asthma is needed to understand their role in mechanisms of airflow obstruction and to rationally design muco-active treatments.METHODSCT lung scans from 57 patients with asthma were analyzed to quantify mucus plug size and airway location, and paired CT scans obtained 3 years apart were analyzed to determine plug behavior over time. Radiologist annotations of mucus plugs were incorporated in an image-processing pipeline to generate size and location information that was related to measures of airflow.RESULTSThe length distribution of 778 annotated mucus plugs was multimodal, and a 12 mm length defined short ("stubby", ≤12 mm) and long ("stringy", >12 mm) plug phenotypes. High mucus plug burden was disproportionately attributable to stringy mucus plugs. Mucus plugs localized predominantly to airway generations 6-9, and 47% of plugs in baseline scans persisted in the same airway for 3 years and fluctuated in length and volume. Mucus plugs in larger proximal generations had greater effects on spirometry measures than plugs in smaller distal generations, and a model of airflow that estimates the increased airway resistance attributable to plugs predicted a greater effect for proximal generations and more numerous mucus plugs.CONCLUSIONPersistent mucus plugs in proximal airway generations occur in asthma and demonstrate a stochastic process of formation and resolution over time. Proximal airway mucus plugs are consequential for airflow and are in locations amenable to treatment by inhaled muco-active drugs or bronchoscopy.TRIAL REGISTRATIONClinicaltrials.gov; NCT01718197, NCT01606826, NCT01750411, NCT01761058, NCT01761630, NCT01716494, and NCT01760915.FUNDINGAstraZeneca, Boehringer-Ingelheim, Genentech, GlaxoSmithKline, Sanofi-Genzyme-Regeneron, and TEVA provided financial support for study activities at the Coordinating and Clinical Centers beyond the third year of patient follow-up. These companies had no role in study design or data analysis, and the only restriction on the funds was that they be used to support the SARP initiative.

Predictive Value of Coronary Artery Calcium in Patients Receiving Computed Tomography Pulmonary Angiography for Suspected Pulmonary Embolism in the Emergency Department.

PURPOSE: Coronary artery calcium (CAC) is a frequent incidental finding on computed tomography pulmonary angiogram (CTPA) in the evaluation of pulmonary embolism (PE) in the emergency department (ED); however, its prognostic value is unclear. In this study, we interrogate the prognostic value of CAC identified on CTPA in predicting adverse outcomes in the evaluation of PE in the ED. MATERIALS AND METHODS: In this retrospective cohort study, we identified 610 patients presenting to the ED in 2013 and evaluated with CTPA for suspected PE. Ordinal CAC scores were evaluated as absent (0), mild (1), moderate (2), or severe (3) in each of the 4 main coronary arteries. Composite CAC scores were subsequently compared against adverse clinical outcomes, defined as intensive care unit admission, hospital stay longer than 72 hours, or death during hospital course or at 6-month follow-up, using univariate and multivariate logistic regression analyses. Relevant exclusion criteria included a history of cardiovascular disease. RESULTS: In all, 365 patients met the inclusion criteria (231 women, mean age 56±16 y) with 132 patients (36%) having some degree of CAC and 16 (4%) having severe CAC. Known malignancy was present in 151 (41%) patients and composite adverse clinical outcomes were observed in 98 patients (32%). Age, presence of acute PE, malignancy, and presence of CAC were significant predictors of adverse outcomes on both univariate and multivariate analyses. CAC was not an independent predictor of short-term adverse outcomes on multivariate analysis ( P =0.06) when all patients were considered. However, when patients with known malignancy were excluded, CAC was an independent predictor of short-term adverse outcomes (odds ratio=2.5, confidence interval=1.1-5.5, P =0.03) independent of age and presence of PE. CONCLUSION: The presence of CAC on CT PA was predictive of adverse outcomes in patients without known cardiac disease presenting to the ED with suspected PE.

Imaging Thoracic Aortic Aneurysm.

High-quality aortic imaging plays a central role in the management of patients with thoracic aortic aneurysm. Computed tomography angiography and magnetic resonance angiography are the most commonly used techniques for thoracic aortic aneurysm diagnosis and imaging surveillance, with each having unique strengths and limitations that should be weighed when deciding patient-specific applications. To ensure optimal patient care, imagers must be familiar with potential sources of artifact and measurement error, and dedicate effort to ensure high-quality and reproducible aortic measurements are generated. This review summarizes the imaging evaluation and underlying pathology relevant to the diagnosis of thoracic aortic aneurysm.

Approach to Abnormal Chest Computed Tomography Contrast Enhancement in the Hospitalized Patient.

This article describes an approach to analyzing the distribution of intravenous contrast on chest computed tomography and illustrates the various pathologies and pitfalls that may be encountered by the imager, especially in the hospitalized patient. Understanding normal and abnormal distribution of intravenous contrast can be used as a clue to detect alterations in physiology and flow.

Are Women Disproportionately Represented in Education Compared to Other Roles in Academic Radiology?

RATIONALE AND OBJECTIVES: Women in academic medicine, and radiology specifically, are underrepresented in departmental leadership roles and achieve fewer professional metrics of success. We have observed, however, that women are more broadly represented in medical education leadership. The purpose of this study was to determine if women in academic radiology are overrepresented in educational scholarship and educational leadership compared to general research scholarship and leadership positions, and to determine if there is any difference in the distribution of women in these roles compared to internal medicine. MATERIALS AND METHODS: We performed a PubMed search of education articles in radiology and internal medicine over the last 5 years, and the gender of the authors was determined. Data on gender for authorship of general research topics, departmental leaders, and society leadership was obtained via literature and internet searches and the data was aggregated. Representation ratios (RR of 1.0 = parity) were obtained via risk ratio calculation to compare education versus general scholarship, and the distribution of leadership roles within and between these fields. RESULTS: Women make up 28.5% of academic radiologists and 40.1% of academic internists. A higher proportion of education articles were first authored by women than would be expected in both fields with an RR of 1.46 (p < 0.001) in radiology and 1.23 (p < 0.001) in internal medicine. This overrepresentation was significant compared to general research scholarship in both fields (p < 0.001). In both fields, women were overrepresented in the position of Medical Student Director (RR of 1.47 and 1.22, respectively). For Program Directors, women were overrepresented in radiology (RR of 1.12) and underrepresented in internal medicine (RR of 0.69-0.75). Women in radiology were overrepresented in education society leadership (RR = 1.63) compared to general society leadership (0.98, p = 0.001). CONCLUSION: We found that women in radiology are overrepresented in authorship of education articles, and in departmental and society education leadership roles. This trend was also seen in internal medicine, suggesting that women are more broadly represented in medical education.

A case of acute onset gigantomastia in a 20-year-old woman.

Gigantomastia is an abnormal and rare breast condition characterized by excessive breast tissue growth that can result in physical and psychosocial debilitation. While the etiology is not fully understood, it is postulated that abnormal endogenous hormone stimulation plays a contributory role and often requires mastectomy for definitive treatment. Proliferation of all elements is commonly observed, including glands, ducts, stroma, fat, vessels and skin. Pseudoangiomatous stromal hyperplasia (PASH) is an additional benign breast disease defined microscopically by proliferation of mammary stroma. PASH often clinically presents as an incidental finding while evaluating other benign or malignant lesions, or less commonly as a palpable, well-circumscribed breast mass. Uncommon cases have been reported in which PASH presents as a bilateral, diffuse process. In this case presentation, we report a rare case of a 20-year-old woman presenting with acute onset gigantomastia most likely due to diffuse PASH.

Pericardial Fat Enhancement: New Computed Tomography Biomarker Influences the Relationship Between Pericardial Fat and Coronary Artery Disease.

PURPOSE: Studies have shown a modest association between pericardial fat volume (PFV) and coronary artery disease (CAD), potentially mediated by local inflammation. We aimed to investigate the association between a new biomarker of pericardial fat inflammation, named pericardial fat enhancement (PFE), and the severity of CAD on coronary computed tomography angiography (CCTA). MATERIALS AND METHODS: We evaluated 114 patients referred for CCTA from 2007 to 2011. PFV, presence of obstructive CAD, and the burden of CAD were determined. PFE was measured in 10 mm regions of interest, adjusted to aortic enhancement (aPFE). The population was divided into those with greater than median (G-PFE) versus less than median pericardial fat enhancement (L-PFE). Stratified adjusted logistic regressions were performed. A P-value <0.05 was considered significant. The study was approved by our institutional review board. RESULTS: Patients were 54.3±14.8 years of age, and 57/114 (50%) were male individuals, with body mass index of 27.3±6.3. There was an independent association between CAD severity and PFV. There was a significant independent association between PFV and obstructive CAD (odds ratio=1.26, P=0.005), and PFV and burden of CAD (odds ratio=1.25, P=0.05) in those with greater PFE. However, there was no significant association between obstructive CAD and CAD burden in either adjusted model for patients with less PFE. CONCLUSIONS: Our results suggest that PFE influences significantly the relationship between PFV and CAD, supporting the hypothesis of local pericardial fat inflammation as a mechanism for CAD development.

Dedicated Diagnostic Radiology/Radiation Oncology Rounds: Added Value Beyond Traditional Tumor Boards.

OBJECTIVES: We aimed to evaluate the impact of collaborative discussion between diagnostic radiologists and radiation oncologists on radiation oncology management for thoracic oncology patients. METHODS: We reviewed cases presented at multidisciplinary thoracic tumor boards (TTB) (n = 122) and diagnostic radiology/radiation oncology rounds (DR/ROR) (n = 45). Changes in planned radiation management following imaging discussion were categorized-no change, timing change, and treatment volume change. Phase of care was also classified. In DR/ROR, radiation oncologists were surveyed regarding (1) change in radiation oncology management and (2) change in confidence (both 5-point Likert scales). RESULTS: Discussion of imaging with a radiologist changed radiation oncology management in 31.1% of TTB cases and 68.9% of DR/ROR cases (P < 0.001). Changes to the timing of initiating radiation therapy occurred with similar frequency in the 2 settings (31.1% vs 46.7%, P = 0.063). Changes to target volume occurred more frequently in DR/ROR (35.6% vs <1%), P < 0.001. Over half of imaging discussions in DR/ROR resulted in at least "moderate" change in radiation oncology management, and the level of confidence held by the radiation oncologists increased following discussion with radiologists in 95.6% of cases. CONCLUSION: Collaborative discussions between radiation oncologists and diagnostic radiologists in a multispecialty tumor board and in targeted 2-specialty rounds are not redundant, but result in different management changes and at different phases of care. Our study emphasizes the importance of consultation with physicians as an area where radiologists can add value, specifically the added benefit of smaller collaborative discussions.

Imaging of the Thoracic Manifestations of Connective Tissue Disease.

Imaging, specifically computed tomography (CT), is a key component in the characterization, management, and follow-up of patients with connective tissue disease (CTD)-related diffuse lung disease. The main role of CT is to help direct treatment by determining the primary pattern of lung injury present. Other roles include follow-up of lung disease over time, evaluation of acute symptoms, and monitoring for treatment complications. Although diagnosis is typically made using clinical and serologic criteria, CT plays an important role when lung disease is the dominant presenting feature. This article delineates the roles of CT in patients with CTD-related lung disease.

Nonischemic Cardiomyopathies.

Computed tomography of the heart can characterize and differentiate various forms of nonischemic cardiomyopathy, which are covered individually in this article. With its excellent spatial and ever-improving temporal resolution, computed tomography scanning can delineate cardiac function, anatomy, and myocardial tissue characterization. Various cardiac computed tomography techniques can be tailored to the relevant clinical question, as discussed in the article. Although cardiac computed tomography scanning is not often the primary modality for myocardial evaluation, decreasing radiation doses and emerging applications make this fast and relatively economical examination a useful tool in the evaluation of the patient with cardiomyopathy.

Smoking-Related Lung Disease.

Smoke from cigarettes and other sources may induce a variety of patterns of lung injury. While smoking related lung diseases, in general, have a better prognosis than many other diffuse lung diseases, they may be a cause of significant symptoms and, in some cases, may even require lung transplantation. On histology, the manifestations of these patterns range from reversible inflammation to irreversible emphysema or fibrosis. High-resolution chest CT plays a critical role in the diagnosis of smoking related lung diseases. It has several roles including (1) helping determine diagnosis, (2) assessing the pattern of injury that is present, (3) evaluating the extent and severity of disease, and (4) determining the response to treatment. The practicing radiologist must have a knowledge of the clinical, pathologic, and imaging features of the differnent patterns of lung injury associated with smoke inhalation.

Interest in Interventional Radiology at Different Stages of Training: Possible Implications for the New Integrated Interventional Radiology Residency.

PURPOSE: Integrated interventional radiology (IR) residencies recently underwent their second year in the match, the first year of which involved only a limited number of programs. Now that students can choose to enter IR directly, student perceptions of IR vs diagnostic radiology (DR) are of paramount importance. METHODS: We surveyed first- through fourth-year medical students and radiology residents regarding interest in IR vs DR. RESULTS: Students considering a radiological career expressed more interest in IR than DR. Conversely, residents expressed more interest in DR. CONCLUSIONS: Medical student advisors and IR programs should continue to anticipate a high number of applications for integrated IR positions.

The role of high-resolution computed tomography in the follow-up of diffuse lung disease: Number 2 in the Series "Radiology" Edited by Nicola Sverzellati and Sujal Desai.

High-resolution computed tomography (HRCT) of the lung is a key component of the multidisciplinary approach to diagnosis in diffuse lung disease (DLD). HRCT also plays an important role in the follow-up of patients with established DLD. In this respect, serial HRCT examinations may provide valuable information that cannot be determined from clinical history and other diagnostic tests, such as pulmonary function tests. Important roles of HRCT in this context include assisting in determining prognosis, monitoring for the efficacy of treatment, detecting progression of disease or complications, and evaluating patients with worsening or acute symptoms. Both clinicians and radiologists should be aware of the expected evolution of HRCT changes in a variety of DLDs. The goals of this paper are to discuss: 1) the expected evolution of HRCT findings over time in common DLDs; 2) the role of serial HRCT examinations in formulating an initial diagnosis; and 3) the role of HRCT in the follow-up of patients with known DLD.

Instituting a Low-dose CT-guided Lung Biopsy Protocol.

RATIONALE AND OBJECTIVES: We aimed to evaluate whether implementation of a low-dose computed tomography (CT)-guided lung biopsy protocol, with the support of individual radiologists in the section, would lead to immediate and sustained decreases in radiation dose associated with CT-guided lung biopsies. MATERIALS AND METHODS: A low-dose CT-guided lung biopsy protocol was developed with modifications of kilovoltage peak, milliamperes, and scan coverage. Out of 413 CT-guided lung biopsies evaluated over a 3-year period beginning in 2009, 175 performed with a standard protocol before the development of a low-dose protocol, and 238 performed with a low-dose protocol. The dose-length product (DLP) was recorded for each lung biopsy and retrospectively compared between the two protocols. Individual radiologist level DLPs were also compared before and after the protocol change. RESULTS: The mean biopsy dose decreased by 64.4% with the low-dose protocol (113.8 milligray centimeters versus 319.7 milligray centimeters; P < 0.001). This decrease in radiation dose persisted throughout the entire 18 months evaluated following the protocol change. After the protocol change, each attending radiologist demonstrated a decrease in administered radiation dose. The diagnostic outcome rate and complication rate were unchanged over the interval. CONCLUSIONS: Implementation of a low-dose CT-guided lung biopsy protocol resulted in an immediate reduction in patient radiation dose that was seen with all attending radiologists and persisted for at least 18 months. Such an intervention may be considered at other institutions wishing to reduce patient doses.

The VEGF receptor Flt-1 spatially modulates Flk-1 signaling and blood vessel branching.

Blood vessel formation requires the integrated regulation of endothelial cell proliferation and branching morphogenesis, but how this coordinated regulation is achieved is not well understood. Flt-1 (vascular endothelial growth factor [VEGF] receptor 1) is a high affinity VEGF-A receptor whose loss leads to vessel overgrowth and dysmorphogenesis. We examined the ability of Flt-1 isoform transgenes to rescue the vascular development of embryonic stem cell-derived flt-1-/- mutant vessels. Endothelial proliferation was equivalently rescued by both soluble (sFlt-1) and membrane-tethered (mFlt-1) isoforms, but only sFlt-1 rescued vessel branching. Flk-1 Tyr-1173 phosphorylation was increased in flt-1-/- mutant vessels and partially rescued by the Flt-1 isoform transgenes. sFlt-1-rescued vessels exhibited more heterogeneous levels of pFlk than did mFlt-1-rescued vessels, and reporter gene expression from the flt-1 locus was also heterogeneous in developing vessels. Our data support a model whereby sFlt-1 protein is more efficient than mFlt-1 at amplifying initial expression differences, and these amplified differences set up local discontinuities in VEGF-A ligand availability that are important for proper vessel branching.