Search

Introduction: Identify the risk factors for delayed pneumothorax after lung biopsy. Methods: A retrospective study of 355 CT‐guided lung biopsies was performed at Fiona Stanley Hospital, Western Australia over 42 months. A comprehensive range of patient, lesion and procedural variables were recorded. All post‐procedural complications including time, size of pneumothorax and post‐biopsy radiographs were reviewed. Lasso logistic regression model was utilised to determine factors predicting patient complications. Results: A total of 167 patients (47%) developed a pneumothorax, in which 34% were significant, requiring longer observation or drain insertion. The majority of pneumothoraces occurred within the first hour (86%), with 90% detected at the time of the procedure. Then, 12% were detected more than 3 h post‐procedure, of which 8 patients (5%) had a significant delayed pneumothorax. Factors increasing the likelihood of significant pneumothorax include the length of lung traversed, smaller nodule size, surrounding emphysema, increased age and lateral patient position with the lesion in the non‐dependent aspect. Increasing patient age, longer length of lung traversed and smaller nodule diameter increase the risk of delayed onset of pneumothorax (more than 3 h). Conclusion: The results of this study align with other studies indicating it is safe to discharge stable patients within an hour post‐lung biopsy. However, specific risk factors, including age, small lesion size and deep lesions, may identify patients who could benefit from a longer observation period. [ABSTRACT FROM AUTHOR]

Purpose: Patients with auto-antibodies neutralizing type I interferons (anti-IFN auto-Abs) are at risk of severe forms of coronavirus disease 19 (COVID-19). The chest computed tomography (CT) scan characteristics of critically ill COVID-19 patients harboring these auto-Abs have never been reported. Methods: Bicentric ancillary study of the ANTICOV study (observational prospective cohort of severe COVID-19 patients admitted to the intensive care unit (ICU) for hypoxemic acute respiratory failure between March 2020 and May 2021) on chest CT scan characteristics (severity score, parenchymal, pleural, vascular patterns). Anti-IFN auto-Abs were detected using a luciferase neutralization reporting assay. Imaging data were collected through independent blinded reading of two thoracic radiologists of chest CT studies performed at ICU admission (± 72 h). The primary outcome measure was the evaluation of severity by the total severity score (TSS) and the CT severity score (CTSS) according to the presence or absence of anti-IFN auto-Abs. Results: Two hundred thirty-one critically ill COVID-19 patients were included in the study (mean age 59.5 ± 12.7 years; males 74.6%). Day 90 mortality was 29.5% (n = 72/244). There was a trend towards more severe radiological lesions in patients with anti-IFN auto-Abs than in others, not reaching statistical significance (median CTSS 27.5 (21.0–34.8) versus 24.0 (19.0–30.0), p = 0.052; median TSS 14.5 (10.2–17.0) versus 12.0 (9.0–15.0), p = 0.070). The extra-parenchymal evaluation found no difference in the proportion of patients with pleural effusion, mediastinal lymphadenopathy, or thymal abnormalities in the two populations. The prevalence of pulmonary embolism was not significantly different between groups (8.7% versus 5.3%, p = 0.623, n = 175). Conclusion: There was no significant difference in disease severity as evaluated by chest CT in severe COVID-19 patients admitted to the ICU for hypoxemic acute respiratory failure with or without anti-IFN auto-Abs. [ABSTRACT FROM AUTHOR]

Single-photon-emission-computerized-tomography/computed-tomography(SPECT/CT) is commonly used for pulmonary disease. Scant work has been done to determine ability of AI for secondary findings using low-dose-CT(LDCT) attenuation correction series of SPECT/CT. 120 patients with ventilation-perfusion-SPECT/CT from 9/1/21–5/1/22 were included in this retrospective study. AI-RAD companion(VA10A,Siemens-Healthineers, Erlangen, Germany), an ensemble of deep-convolutional-neural-networks was evaluated for the detection of pulmonary nodules, coronary artery calcium, aortic ectasia/aneurysm, and vertebral height loss. Accuracy, sensitivity, specificity was measured for the outcomes. Inter-rater reliability were measured. Inter-rater reliability was measured using the intraclass correlation coefficient (ICC) by comparing the number of nodules identified by the AI to radiologist. Overall per-nodule accuracy, sensitivity, and specificity for detection of lung nodules were 0.678(95%CI 0.615–0.732), 0.956(95%CI 0.900–0.985), and 0.456(95%CI 0.376–0.543), respectively, with an intraclass correlation coefficient (ICC) between AI and radiologist of 0.78(95%CI 0.71–0.83). Overall per-patient accuracy for AI detection of coronary artery calcium, aortic ectasia/aneurysm, and vertebral height loss was 0.939(95%CI 0.878–0.975), 0.974(95%CI 0.925–0.995), and 0.857(95%CI 0.781–0.915), respectively. Sensitivity for coronary artery calcium, aortic ectasia/aneurysm, and vertebral height loss was 0.898(95%CI 0.778–0.966), 1 (95%CI 0.958–1), and 1 (95%CI 0.961–1), respectively. Specificity for coronary artery calcium, aortic ectasia/aneurysm, and vertebral height loss was 0.969(95% CI 0.893–0.996), 0.897 (95% CI 0.726–0.978), and 0.346 (95% CI 0.172–0.557), respectively. AI ensemble was accurate for coronary artery calcium and aortic ectasia/aneurysm, while sensitive for aortic ectasia/aneurysm, lung nodules and vertebral height loss on LDCT attenuation correction series of SPECT/CT. • Artificial intelligence identifies pulmonary nodules, coronary artery calcium, aortic ectasia/aneurysm, and vertebral height loss on low-dose CT of SPECT/CT. • Use of deep learning on low-dose CT series of ventilation and perfusion SPECT/CT imaging for the identification of incidental findings. • Artificial intelligence identifies pulmonary nodules on low-dose CT series of SPECT/CT. • Artificial intelligence screens for coronary artery calcium and aortic ectasia/aneurysm on low-dose CT series of SPECT/CT. [ABSTRACT FROM AUTHOR]

Summary: Air trapping is a common finding radiologists encounter on CT imaging of the thorax. This term is used when there are geographic areas of differing attenuation within the lung parenchyma. Most commonly, this is the result of abnormal retention of air due to complete or partial airway obstruction from small airway pathologies. Perfusional differences due to underlying vascular diseases could also result in these appearances, and hence, inspiratory and full expiratory phase CT studies are required to accurately diagnose air trapping. It is important to note that this can occasionally be present in healthy patients. Multiple diseases are associated with air trapping. Determining the aetiology relies on accurate patient history and concomitant findings on CT. There is currently no consensus on accurate assessment of the severity of air trapping. The ratio of mean lung density between expiration and inspiration on CT and the change in lung volume have demonstrated a positive correlation with the presence of small airway disease. Treatment and resultant patient outcome depend on the underlying aetiology, and hence, radiologists need to be familiar with the common causes of air trapping. This paper outlines the most common disease processes leading to air trapping, including Constrictive bronchiolitis, Hypersensitivity pneumonitis, DIPNECH, and Post‐infectious (Swyer‐James/Macleod). Various diseases result in the air trapping pattern seen on the expiratory phase CT scan of the thorax. Combining patient history with other concomitant imaging findings is essential for accurate diagnosis and to further guide management. [ABSTRACT FROM AUTHOR]

Background: Asymptomatic, isolated cases of unilateral pulmonary artery atresia may present in adulthood with symptoms such as recurrent respiratory infections, dyspnea, hemoptysis, and pulmonary hypertension. Unlike previously reported patients that underwent surgical management for this pathology, the patient in this report had no chronic history of recurrent respiratory infections, dyspnea, or pulmonary hypertension, making a diagnosis prior to extensive imaging difficult. Case presentation: A 55-year-old male presented to our emergency department (ED) with a 3-day history of recurrent cough with 2–3 tablespoons of hemoptysis per episode, chills, and occasional wheezing. A computed tomography angiography (CTA) was performed, which identified a congenital absence of the left pulmonary artery and a right-sided aortic arch. Hypertrophied left intercostal and bronchial arteries were noted to be perfusing the left lung. V/Q scan confirmed a heterogeneous distribution of gas throughout both lung fields with 97% perfusion to the right lung, but no visualization of the left lung on the perfusion images. Given extensive collateral blood supply to the left lung, interventional radiology performed a GELFOAM® embolization of the hypertrophied left bronchial artery and two parasitized arteries from the left subclavian artery to minimize intra-operative blood loss. This was immediately followed by a left thoracotomy, pneumonectomy, intercostal muscle flap placement, and bronchoscopy. The procedure was 360 min long with a total of 1500 cc blood loss that was salvaged and re-infused. No additional blood products were administered. The patient remained intubated post-operatively and was transferred to the surgical intensive care unit. His postoperative course was complicated by troponin leak, rhabdomyolysis, delirium, and ileus, all of which resolved over time. He was discharged home on postoperative day seven and continues to do well one-year later. Conclusions: The patient in this report presented with several episodes of isolated hemoptysis but unlike previously reported cases of unilateral pulmonary artery atresia, he had no history of recurrent respiratory infections, dyspnea, or pulmonary hypertension. Although unilateral pulmonary artery atresia is a rare diagnosis, in patients with unexplained, isolated hemoptysis, further examination of the vasculature may be warranted, and surgical management may be beneficial in appropriate, symptomatic patients. [ABSTRACT FROM AUTHOR]

Background: Non-small-cell lung cancer (NSCLC) is a common, steady growing lung tumour that is often discovered when a surgical approach is forbidden. For locally advanced inoperable NSCLC, the clinical approach consists of a combination of chemotherapy and radiotherapy, eventually followed by adjuvant immunotherapy, a treatment that is useful but may cause several mild and severe adverse effect. Chest radiotherapy, specifically, may affect the heart and coronary artery, impairing heart function and causing pathologic changes in myocardial tissues. The aim of this study is to evaluate the damage coming from these therapies with the aid of cardiac imaging. Methods: This is a single-centre, prospective clinical trial. Patients with NSCLC who are enrolled will undergo computed tomography (CT) and magnetic resonance imaging (MRI) before chemotherapy 3 months, 6 months, and 9–12 months after the treatment. We expect to enrol 30 patients in 2 years. Conclusions: Our clinical trial will be an opportunity not only to highlight the timing and the radiation dose needed for pathological cardiac tissue changes to happen but will also provide useful data to set new follow-up schedules and strategies, keeping in mind that, more often than not, patients affected by NSCLC may present other heart- and lung-related pathological conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] As the field of cardiac imaging has demonstrated exceptional growth over the past several decades, radiology departments and residency programs have struggled to integrate cardiac imaging instruction into training curricula. To create an integrated cardio-thoracic teaching and lecture curriculum and resident rotation in accordance with AGGME and Society of Thoracic Radiology (STR) guidelines. Consecutive PGY-2 to PGY-4 residents (n = 14) rotating through our Cardiothoracic Imaging (CTI) section from 1/1/2021 to 04/18/2022 were give pre- and post- rotation tests of knowledge and feedback evaluations. Attending feedback of the curriculum was obtained at 3-months and 9-months post curriculum implementation. A Wilcxon test was used to evaluate differences in improvement between pre- and post- rotation resident feedback scores, test scores for thoracic and cardiac test questions in addition to attending feedback scores at 3 and 9-months post curriculum implementation. The overall post-rotation scores in addition to thoracic only and cardiac only scores improved, with the difference between improved versus stable or decreased scores being statistically significant overall (P = 0.039) and for cardiac scores (P = 0.003), but not for thoracic scores (P = 0.22). The overall (P = 0.002), thoracic (P = 0.027), and cardiac (P = 0.026) resident feedback scores were significantly improved post-rotation. Similarly, the overall attending feedback scores significantly improved over time (P = 0.021). An integrated Cardio-thoracic Imaging teaching curriculum was well received by both residents and attendings with significant improvement in post rotation feedback scores by both groups. Moreover, residents demonstrated improved scores on knowledge tests post rotation. [ABSTRACT FROM AUTHOR]

Introduction: Vaccination against the global pandemic coronavirus disease 2019 (COVID-19) is a promising way out of the havoc caused by the disease. The clinico-radiological profile of COVID-19 patients in relation to the vaccination status is depicted in the present study. Materials and Methods: This is a retrospective observational imaging and hospital data-based study performed on 214 confirmed and clinically suspicious patients of COVID-19 who underwent high-resolution computed tomography (HRCT) scan of the thorax at the Department of Radio-Diagnosis of a tertiary medical center in the Himalayan foothills. The present study aims to evaluate the effect of vaccination on HRCT findings of COVID-19 populations. Results: Forty-three percent of the non-vaccinated population presented with severe HRCT scores (19–25) in comparison to only 11.5% of the study population who had taken both doses of vaccine (P = 0.018). Two doses of vaccination had a negative Pearson correlation coefficient with severe HRCT scores (–0.146). Co-morbidities had a significant correlation with HRCT severity score, with 61.5% diabetics and 63.33% of hypertensive patients showing scores >19 on HRCT. Conclusion: Vaccination proves to be a game changer in the pandemic with two doses of vaccination having a significant negative correlation with COVID-19-induced severe pneumonitis on HRCT of the thorax. [ABSTRACT FROM AUTHOR]

Background: The necessity to identify and isolate COVID-19 patients to avoid intrahospital cross infections is particularly felt as a challenge. Clinically occult SARS-CoV-2 infection among patients admitted to the hospital is always considered a risk during the pandemic. The aim of our study is to describe the application of CT scan to reveal unexpected COVID-19 in patients needing hospital admission. Method: In our emergency department, we prospectively enrolled adult patients needing hospital admission, without symptoms suspected of COVID-19, and showing negative reverse transcriptase-polymerase chain reaction (RT-PCR) swab test. CT scan was performed to diagnose clinically occult COVID-19 pneumonia. All the exams were read and discussed retrospectively by two expert radiologists and assigned to one of 4 exclusive diagnoses: typical (typCT), indeterminate (indCT), atypical (atyCT), negative (negCT). The clinical characteristics and final diagnoses were described and compared with the results of CT scans. Results: From May 25 to August 18, 2020, we prospectively enrolled 197 patients. They showed 122 negCT, 52 atyCT, 22 indCT, and 1 typCT. Based on the CT imaging, the prevalence of suspected clinically occult COVID-19 pneumonia was 11.6% (23 patients). None had confirmation of SARS-CoV-2 infection after the hospital stay. Nineteen patients had negative serial RT-PCR while in 4 cases, the infection was excluded by clinical follow-up or appearance of positivity of RT-PCR after months. Conclusion: Our descriptive analysis confirms that CT scan cannot be considered a valid tool to screen clinically occult COVID-19, when the asymptomatic patients need hospitalization for other conditions. Application of personnel protections and distancing among patients remains the best strategies to limit the possibility of intrahospital cross-infections. [ABSTRACT FROM AUTHOR]

To explore the frequency of superior scapular elastofibroma dorsi in a large patient series with elastofibroma dorsi. 136 chest CTs from January 2016 to July 2022 reporting elastofibroma dorsi were retrospectively analyzed. Three radiologists assessed the number, size, and location of elastofibroma dorsi. Continuous variables underwent two-tailed t -tests with p < 0.05. Inter-observer agreement was assessed by using Cohen's Kappa values. In 136 patients (mean age, 75.9 +/− 9.8 years; 117 female), 330 elastofibroma dorsi were found. Six (4.4 %) patients had single, 87 (64 %) double, 22 (16.2 %) triple and 21 (15.4 %) quadruple lesions. All single and double lesions were in the inferior scapular regions. 43 (31.6 %) patients had superior scapular lesions in addition to inferior scapular elastofibroma dorsi. Inferior scapular elastofibroma dorsi was significantly larger than superior scapular elastofibroma dorsi. The probability of a right superior lesion was significantly higher in patients with a larger right inferior lesion. Inter-observer agreement was very good for experienced radiologist (κ = 94.1) and good for other radiologists (κ = 79.4 and κ = 78). In contrast to current belief, superior scapular elastofibroma dorsi accompanying the typical inferior scapular lesions is not uncommon and can even manifest bilaterally. To the best of our knowledge, this is the first case series reporting prevalence of quadruple elastofibroma dorsi. • Quadruple elastofibroma dorsi prevalance is identified in this study, a novel finding not previously documented. • Elastofibroma dorsi can also be observed in the superior scapular region and can occur up to four simultaneous lesions. • Superior scapular elastofibroma dorsi commonly accompanies typical inferior lesions. • There is a higher probability of having a superior scapular ED in patients with a large size inferior scapular ED. [ABSTRACT FROM AUTHOR]

Background: To develop a deep-learning (DL) pipeline that allowed an automated segmentation of epicardial adipose tissue (EAT) from low-dose computed tomography (LDCT) and investigate the link between EAT and COVID-19 clinical outcomes. Methods: This monocentric retrospective study included 353 patients: 95 for training, 20 for testing, and 238 for prognosis evaluation. EAT segmentation was obtained after thresholding on a manually segmented pericardial volume. The model was evaluated with Dice coefficient (DSC), inter-and intraobserver reproducibility, and clinical measures. Uni-and multi-variate analyzes were conducted to assess the prognosis value of the EAT volume, EAT extent, and lung lesion extent on clinical outcomes, including hospitalization, oxygen therapy, intensive care unit admission and death. Results: The mean DSC for EAT volumes was 0.85 ± 0.05. For EAT volume, the mean absolute error was 11.7 ± 8.1 cm3 with a non-significant bias of −4.0 ± 13.9 cm3 and a correlation of 0.963 with the manual measures (p < 0.01). The multivariate model providing the higher AUC to predict adverse outcome include both EAT extent and lung lesion extent (AUC = 0.805). Conclusions: A DL algorithm was developed and evaluated to obtain reproducible and precise EAT segmentation on LDCT. EAT extent in association with lung lesion extent was associated with adverse clinical outcomes with an AUC = 0.805. [ABSTRACT FROM AUTHOR]

Background: Reports of clinicopathologic features of bronchomalacia (BM) differ because of inconsistent definitions and frequent prevalence of comorbid cardiopulmonary disease. Pulmonary hypertension (PH) secondary to BM is poorly described. Objectives: Dogs with BM will be older but of any somatotype, and increased expiratory effort, ≥1 comorbid disease, and PH will be more common than in dogs without BM. Animals: Client‐owned dogs (n = 210) evaluated for respiratory signs. Methods: Medical records of dogs with paired inspiratory: expiratory‐breath‐hold computed tomography, tracheobronchoscopy, or both between January 2016 and December 2019 were retrospectively reviewed. Comparisons between dogs with and without BM using Mann‐Whitney rank sum or χ2 tests (P <.05 significant were made). Because of high numbers of variables, criteria with high prevalence (>25%) were identified (n = 10) for univariate analysis (P <.005 significant). Significant variables were submitted for multivariate analysis. Results: Bronchomalacia was identified in 41% of dogs of all sizes/somatotypes; 38% were >10 kg. All dogs with BM had ≥1 comorbid cardiopulmonary disorder. Dogs with BM were significantly older (P <.001), smaller (P <.001), and were more likely diagnosed with tracheal or mainstem bronchial collapse (P <.001) or bronchiectasis (P <.001). Multivariate analysis confirmed associations with age, tracheal or mainstem bronchial collapse, and bronchiectasis. In dogs with BM, PH was more prevalent. Conclusions and Clinical Importance: Although significantly more common in older, smaller dogs, BM occurs in dogs of all sizes and in all instances with comorbidities. Echocardiography should be considered in dogs with BM to identify PH. [ABSTRACT FROM AUTHOR]

Introduction: Spontaneous pneumomediastinum is an uncommon complication of Corona Virus Disease (COVID)-19 presenting mostly in moderate to severe cases. Materials and Methods: This is a retrospective observational imaging and hospital data-based study done on 15 confirmed patients of COVID-19 who underwent high resolution computed tomography (HRCT) thorax at the Department of Radio-Diagnosis of a tertiary medical center in the Himalayan foothills. The clinico-radiological profile of the study group was assessed and it was aimed at finding the association of pneumomediastinum with the severity of lung changes. Results: A strong association of pneumomediastinum was observed with severe lung changes on HRCT thorax (n = 13, 87%, P < 0.00001). Dyspnea was the most common presenting factor. The mortality rate is high in mechanically intubated patients of pneumomediastinum with COVID-19 (75%). Conclusion: Pneumomediastinum is a complication of a severe COVID-19 disease spectrum. Along with severe lung parenchymal disease, systemic inflammation, systemic steroid therapy, comorbid state, and mechanical intubation, it is a part of the pool of poor prognostic factors. HRCT is essential for making a quick and comprehensive diagnosis, thereby, guiding the clinician for further management. [ABSTRACT FROM AUTHOR]

The World Health Organization (WHO) declared the transmission of SARS-CoV-2 a Public Health Emergency of International Concern. The novel coronavirus has diverse manifestations, usually similar to a common cold or influenza. The majority of patients with coronavirus disease have typical imaging features. The typical CT characteristics of patients with COVID-19 pneumonia are ground-glass opacities and consolidative lesions with a peripheral and posterior distribution. Noninvasive imaging methods are precise and rapid means of diagnosing pneumonia and cardiovascular complications caused by COVID-19 infection. Therefore, it is important for clinicians to understand the implications of this pandemic and to be familiar with the different imaging aspects of the novel coronavirus disease. This review focuses on the most commonly reported imaging findings of COVID-19 infection in different patients from different countries, the expert recommendations, and the cardiac manifestations of SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Objectives: Severe coronavirus disease 2019 is associated with an extensive pneumonitis and frequent coagulopathy. We sought the true prevalence of thrombotic complications in critically ill patients with severe coronavirus disease 2019 on the ICU, with or without extracorporeal membrane oxygenation.Design: We undertook a single-center, retrospective analysis of 72 critically ill patients with coronavirus disease 2019-associated acute respiratory distress syndrome admitted to ICU. CT angiography of the thorax, abdomen, and pelvis were performed at admission as per routine institution protocols, with further imaging as clinically indicated. The prevalence of thrombotic complications and the relationship with coagulation parameters, other biomarkers, and survival were evaluated.Setting: Coronavirus disease 2019 ICUs at a specialist cardiorespiratory center.Patients: Seventy-two consecutive patients with coronavirus disease 2019 admitted to ICU during the study period (March 19, 2020, to June 23, 2020).Interventions: None.Measurements and Main Results: All but one patient received thromboprophylaxis or therapeutic anticoagulation. Among 72 patients (male:female = 74%; mean age: 52 ± 10; 35 on extracorporeal membrane oxygenation), there were 54 thrombotic complications in 42 patients (58%), comprising 34 pulmonary arterial (47%), 15 peripheral venous (21%), and five (7%) systemic arterial thromboses/end-organ embolic complications. In those with pulmonary arterial thromboses, 93% were identified incidentally on first screening CT with only 7% suspected clinically. Biomarkers of coagulation (e.g., d-dimer, fibrinogen level, and activated partial thromboplastin time) or inflammation (WBC count, C-reactive protein) did not discriminate between patients with or without thrombotic complications. Fifty-one patients (76%) survived to discharge; 17 (24%) patients died. Mortality was significantly greater in patients with detectable thrombus (33% vs 10%; p = 0.022).Conclusions: There is a high prevalence of thrombotic complications, mainly pulmonary, among coronavirus disease 2019 patients admitted to ICU, despite anticoagulation. Detection of thrombus was usually incidental, not predicted by coagulation or inflammatory biomarkers, and associated with increased risk of death. Systematic CT imaging at admission should be considered in all coronavirus disease 2019 patients requiring ICU. [ABSTRACT FROM AUTHOR]

The clinical scenario of a pulmonary nodule following lung transplantation is one with limited experience and no supporting guidelines for the approach to diagnosis and management. Given the broad differential diagnosis for pulmonary nodules in this setting, most of which are life-threatening without appropriate treatment, aggressive evaluation is required. Here we present a case of a 70-year-old female with the development of a large pulmonary nodule in the native lung four years following a single lung transplant. She underwent bronchoscopy with endobronchial ultrasound to achieve a tissue diagnosis which showed small cell lung carcinoma. The patient was started on chemotherapy and has shown clinical and radiographic improvement at most recent follow up seven months after the initial diagnosis. In this report we discuss the differential diagnosis and corresponding imaging findings for the pulmonary nodule following lung transplantation to aid in guiding clinicians navigate this challenging clinical situation. • Pulmonary nodules following lung transplantation require aggressive evaluation. • There is limited experience and no guidelines for this clinical scenario. • The differential diagnosis is broad and the cause is generally life-threatening. • The most common etiologies are malignancy and infection. [ABSTRACT FROM AUTHOR]

An approximately 1‐year‐old male intact Shih Tzu dog was referred to a tertiary facility with a history of progressive tachypnea, increased respiratory effort, and weight loss over a 3‐month period that failed to improve with empirical antimicrobial treatment. Upon completion of a comprehensive respiratory evaluation, the dog was diagnosed with severe Pneumocystis pneumonia and secondary pulmonary hypertension. Clinical signs resolved and disease resolution was confirmed after completion of an 8‐week course of trimethoprim‐sulfonamide, 4‐week tapering dose of prednisone to decrease an inflammatory response secondary to acute die‐off of organisms, a 2‐week course of clopidogrel to prevent clot formation, and a 2‐week course of a phosphodiesterase‐5 inhibitor to treat pulmonary hypertension. Immunodiagnostic testing and genetic sequencing were performed to evaluate for potential immunodeficiency as an underlying cause for the development Pneumocystis pneumonia, and identified an X‐linked CD40 ligand deficiency. [ABSTRACT FROM AUTHOR]

Purpose: Chronic obstructive pulmonary disease (COPD) affects ∼200 million people worldwide. We propose two‐dimensional (2D) dual‐energy (DE) x‐ray imaging of lung structure and function for the assessment of COPD, and investigate the resulting image quality theoretically. Methods: We investigated xenon‐enhanced DE (XeDE) radiography for functional imaging of COPD and unenhanced DE radiography for structural imaging of COPD. We modeled the ability of human observers to detect ventilation defects in XeDE images and emphysema in (unenhanced) DE images using the detectability index (d′) as a figure of merit. We accounted for the extent of emphysematous destruction and functional impairment as a function of disease severity, defect/lesion contrast, spatial resolution, x‐ray scatter, quantum noise, anatomic noise, and the efficiency of human observers. Whether or not disease was detectable was determined based on a detectability threshold of two. For (unenhanced) DE imaging of emphysema, we compared detectability with that of single‐energy (SE) imaging. Models of signal and noise were compared to published data. Results: Models of signal and noise agreed well with published data, and model predictions of the detectability of emphysema by SE radiography were consistent with poor sensitivity (i.e., d′<1) to mild to moderate COPD but moderate sensitivity (i.e., d′>1.5) to severe COPD. The detectability of emphysema by DE radiography was greater than that of SE radiography, but did not cross the threshold of detectability for mild to moderate COPD. The detectability index for XeDE imaging exceeded the detectability threshold for mild, moderate, and severe COPD. Conclusions: Dual‐energy radiography may offer modest improvements in the detection of emphysema relative to SE imaging, but will unlikely enable detecting mild and moderate COPD. However, XeDE radiography may enable detection of functional abnormalities associated with mild, moderate and severe COPD at x‐ray exposures typical of those used in conventional chest radiography, thus warranting further investigation as a low‐dose, low‐cost alternative to CT‐ and MRI‐based approaches for functional imaging of COPD. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic remains an evolving disease posing a challenge of incomplete understanding escalated by random atypical clinical presentations. Numerous challenges still exist with accessibility and availability of standard COVID-19 viral testing using real-time Polymerase Chain Reaction (RT-PCR), in low- and middle-income countries, especially in several hospital settings. The clinical information of three select patients at a major health facility in Southwestern Nigeria with unusual COVID-19 clinical presentation and clinical management dilemma related to challenges with COVID-19 viral laboratory testing, were retrospectively reviewed. The medical history in all three cases closely mimicked that of other medical conditions because of assumptions created by red herrings like an acute exacerbation of an underlying non-communicable disease (diaphragmatic eventration) in case 1, re-activation of a previously treated lung condition (tuberculosis) in case 2 and a sequalae of a previously diagnosed but poorly-managed chronic non-communicable disease (decompensated hypertensive heart disease). Also, viral testing was challenging in all cases due to reasons ranging from late turn-around time to inconsistent results. However, thoracic imaging was employed in all cases to heighten suspicion of COVID-19 infection, resolve management dilemma and limit intra-hospital spread. Thoracic imaging can play a major role within hospital settings in low-and middle-income countries in resolving diagnostic challenges of atypical COVID-19 clinical presentations, raising suspicion for early institution of intra-hospital disease containment measures, limiting exposure among hospital staff and guiding clinical case management of COVID-19; especially where challenges with confirmatory viral testing remain persistent. [ABSTRACT FROM AUTHOR]

The thoracic inlet is located at the crossroads between imaging of the neck and chest. It represents an important anatomic landmark, serving as the central conducting pathway for many vital structures extending from the neck into the chest and vice versa. Many important body systems are located within this region, including the enteric, respiratory, vascular, lymphatic, neurologic, and endocrine systems. A detailed examination of this region is essential when reviewing neck and thoracic imaging. This article will discuss the normal anatomic boundaries of the thoracic inlet and present an image-rich systematic discussion of the non-neoplastic pathology that can occur in this region. The neoplastic pathology of the thoracic inlet will be covered in a companion article. [ABSTRACT FROM AUTHOR]

The design and performance of the active complex electrode (ACE1) electrical impedance tomography system for single-ended phasic voltage measurements are presented. The design of the hardware and calibration procedures allows for reconstruction of conductivity and permittivity images. Phase measurement is achieved with the ACE1 active electrode circuit which measures the amplitude and phase of the voltage and the applied current at the location at which current is injected into the body. An evaluation of the system performance under typical operating conditions includes details of demodulation and calibration and an in-depth look at insightful metrics, such as signal-to-noise ratio variations during a single current pattern. Static and dynamic images of conductivity and permittivity are presented from ACE1 data collected on tank phantoms and human subjects to illustrate the system’s utility. [ABSTRACT FROM AUTHOR]

Background: Thoracic ultrasound (TUS) has a high diagnostic accuracy for many common pulmonary diseases, but theoretic knowledge in sonographic physics, thoracic anatomy and physiology, and sonopathologic patterns is required to develop competence. Objectives: The aims of the study were to develop and gather validity evidence for a theoretical test in TUS and to establish a pass/fail standard. Methods: Content was provided based on expert interviews, leading to the creation of 113 initial multiple-choice question (MCQ) items. Consensus was reached on 92 proceeding items through a Delphi process, and items were presented to physicians with different knowledge and experience in TUS. Answers were used for item statistics in order to select the items with the most optimal item discrimination and difficulty (i.e., level I items) to be included in the final test. Mean scores of the novice, intermediate and experienced groups were compared, and a pass/fail score was established using the contrasting groups' standard setting method. Results:Item statistics revealed 38 level I items, of which 30 were selected to be included in the final test. The internal consistency was high (Cronbach's alpha = 0.88). Differences in mean scores were 8.6 points (p < 0.001), 6.3 points (p = 0.01), and 14.9 points (p < 0.001) between novices and intermediates, intermediates and experienced, and novices and experienced, respectively. A pass/fail standard of 20 points was established. Conclusion: The established MCQ test can distinguish between physicians with different levels of competence in TUS and enables an objective, evidence-based approach for assessing the theoretical knowledge of trainees undergoing an educational programme in TUS. [ABSTRACT FROM AUTHOR]

Purpose: Accurate photon attenuation assessment from MR data remains an unmet challenge in the thorax due to tissue heterogeneity and the difficulty of MR lung imaging. As thoracic tissues encompass the whole physiologic range of photon absorption, large errors can occur when using, for example, a uniform, water‐equivalent or a soft‐tissue‐only approximation. The purpose of this study was to introduce a method for voxel‐wise thoracic synthetic CT (sCT) generation from MR data attenuation correction (AC) for PET/MR or for MR‐only radiation treatment planning (RTP). Methods: Acquisition: A radial stack‐of‐stars combining ultra‐short‐echo time (UTE) and modified Dixon (mDixon) sequence was optimized for thoracic imaging. The UTE‐mDixon pulse sequence collects MR signals at three TE times denoted as UTE, Echo1, and Echo2. Three‐point mDixon processing was used to reconstruct water and fat images. Bias field correction was applied in order to avoid artifacts caused by inhomogeneity of the MR magnetic field. Analysis: Water fraction and R2* maps were estimated using the UTE‐mDixon data to produce a total of seven MR features, that is UTE, Echo1, Echo2, Dixon water, Dixon fat, Water fraction, and R2*. A feature selection process was performed to determine the optimal feature combination for the proposed automatic, 6‐tissue classification for sCT generation. Fuzzy c‐means was used for the automatic classification which was followed by voxel‐wise attenuation coefficient assignment as a weighted sum of those of the component tissues. Performance evaluation: MR data collected using the proposed pulse sequence were compared to those using a traditional two‐point Dixon approach. Image quality measures, including image resolution and uniformity, were evaluated using an MR ACR phantom. Data collected from 25 normal volunteers were used to evaluate the accuracy of the proposed method compared to the template‐based approach. Notably, the template approach is applicable here, that is normal volunteers, but may not be robust enough for patients with pathologies. Results: The free breathing UTE‐mDixon pulse sequence yielded images with quality comparable to those using the traditional breath holding mDixon sequence. Furthermore, by capturing the signal before T2* decay, the UTE‐mDixon image provided lung and bone information which the mDixon image did not. The combination of Dixon water, Dixon fat, and the Water fraction was the most robust for tissue clustering and supported the classification of six tissues, that is, air, lung, fat, soft tissue, low‐density bone, and dense bone, used to generate the sCT. The thoracic sCT had a mean absolute difference from the template‐based (reference) CT of less than 50 HU and which was better agreement with the reference CT than the results produced using the traditional Dixon‐based data. Conclusion: MR thoracic acquisition and analyses have been established to automatically provide six distinguishable tissue types to generate sCT for MR‐based AC of PET/MR and for MR‐only RTP. [ABSTRACT FROM AUTHOR]

Purpose: Image acquisition protocols and reports in patients with pectus excavatum (PEX) differ significantly from routine examinations, and no imaging modality can enable a comprehensive assessment of PEX severity and cardiac impact within a single examination. We therefore attempt to establish recommendations about preoperative imaging in patients with PEX.Method: Chest computed tomography (CT), stress echocardiography (Echo), and cardiac magnetic resonance (CMR) allow the evaluation of specific information regarding structural and functional characteristics of vital importance to assess surgical candidacy and define surgical strategies. We sought to provide a multidisciplinary state of the art document involving thoracic surgeons, radiologists, and cardiologists; to establish recommendations about the variables to be included in the reports of the imaging examinations performed in patients with PEX.Results: We provide recommendations for preoperative image acquisition and analysis, aimed at the assessment of the severity of the chest wall deformity (CT); the site of maximum cardiac compression, extent of increased interventricular dependence, and presence of pericardial effusion (CMR); and the effect of PEX on the functional capacity and exercise-related systolic and/or diastolic function, and tricuspid annulus compression (Echo).Conclusions: This multidisciplinary state of the art document involving thoracic surgeons, radiologists, and cardiologists provides recommendations about preoperative imaging for patients with PEX. [ABSTRACT FROM AUTHOR]

The thoracic inlet is located at the crossroads between imaging of the neck and chest. It represents an important anatomic landmark, serving as the central conducting pathway for many vital structures extending from the neck into the chest and vice versa. Many important body systems are located within this region, including the enteric, respiratory, vascular, lymphatic, neurologic, and endocrine systems. A detailed examination of this region is essential when reviewing neck and thoracic imaging. This article will discuss the normal anatomic boundaries of the thoracic inlet and present an image-rich systematic discussion of the non-neoplastic pathology that can occur in this region. The neoplastic pathology of the thoracic inlet will be covered in a companion article. [ABSTRACT FROM AUTHOR]

Objectives: Most patients with myasthenia gravis (MG) undergo thoracic imaging at initial diagnosis. However, the follow‐up protocol is unclear. The objective of the present study was to clarify the follow‐up status and main findings of thoracic imaging in patients with MG. Methods: A total of 649 patients with disease duration ≥1 year were included in the study. The follow‐up rate and time from the initial scan to the latest thoracic imaging were evaluated. The rate of abnormality and details of abnormal findings in both non‐thymomatous MG and thymoma‐associated MG were investigated. Results: The follow‐up thoracic imaging rate of 145 patients with thymoma‐associated MG was 71.7%, whereas just 46.2% of 504 patients with non‐thymomatous MG underwent follow‐up imaging. Abnormal findings were detected in 8.6% of patients with non‐thymomatous MG and 26.0% of those with thymoma‐associated MG. Abnormal findings included cancer, lung infection and lymph node swelling in the former, and relapse or increased size of thymoma in the latter. Conclusions: Frequent follow up by thoracic imaging is necessary in patients with MG. The follow‐up thoracic imaging rate of patients with thymoma‐associated MG was 71.7%, whereas only 46.2% of patients with non‐thymomatous MG underwent follow‐up imaging. Abnormal findings were detected in 8.6% of patients with non‐thymomatous MG and 26.0% of those with thymoma‐associated MG. Frequent follow‐up by thoracic imaging is necessary in patients with MG. [ABSTRACT FROM AUTHOR]

Sickle cell disease is an inherited hemolytic disease with systemic complications. These complications significantly impact the patients' quality of life. There are characteristic radiological findings that can aid in the diagnosis and management of common sequelae of sickle cell disease. In this review, we will discuss the thoracic imaging findings of common complications of sickle cell disease in an organ-based approach and provide imaging examples of them. [ABSTRACT FROM AUTHOR]

The occurrence of thymoma in myotonic dystrophy type 1 (DM1) has been occasionally reported, and an increased risk of tumors has been observed. We performed imaging of the thymus in 22 patients carrying DMPK expansion. Clinical examination and routine instrumental exams were performed at the same time. We observed no thymic abnormalities in 13 subjects, thymic hyperplasia in eight patients, and an invasive thymoma in one case. Subjects with thymic abnormalities did not show peculiarities as regards clinical and electrophysiological features. We observed thymoma in one patient with an expansion in the higher range. Abnormalities of the thymus including hyperplasia and thymoma can be present in DM1, but do not seem to play a major role in DM1 pathogenesis. Further studies are needed to understand if some RNA splicing factors involved in DM1 and influenced by CTG expansion size could have a role in thymocytes proliferation. [ABSTRACT FROM AUTHOR]

Objectives: To determine the impact of specific reporting tasks on the performance of radiologists when reading chest radiographs.Methods: Ten experienced radiologists read a set of 40 postero-anterior (PA) chest radiographs: 21 nodule free and 19 with a proven solitary nodule. There were two reporting conditions: an unframed task (UFT) to report any abnormality and a framed task (FT) reporting only lung nodule/s. Jackknife free-response operating characteristic (JAFROC) figure of merit (FOM), specificity, location sensitivity and number of true positive (TP), false positive (FP), true negative (TN) and false negative (FN) decisions were used for analysis.Results: JAFROC FOM for tasks showed a significant reduction in performance for framed tasks (P = 0.006) and an associated decrease in specificity (P = 0.011) but no alteration to the location sensitivity score. There was a significant increase in number of FP decisions made during framed versus unframed tasks for nodule-containing (P = 0.005) and nodule-free (P = 0.011) chest radiographs. No significant differences in TP were recorded.Conclusions: Radiologists report more FP decisions when given specific reporting instructions to search for nodules on chest radiographs. The relevance of clinical history supplied to radiologists is called into question and may induce a negative effect.Key Points: • Framed reporting tasks increases false positive rates when searching for pulmonary nodules • False positive results were observed in both nodule-containing and nodule-free cases • Radiologist's decision-making may be influenced by clinical history in thoracic imaging. [ABSTRACT FROM AUTHOR]

Objective: Current guidelines for the management of renal mass recommend thoracic imaging for potential metastatic nodules. Small size of the renal mass can be associated with low metastatic potential, which might question the necessity of thoracic imaging in this patient population. This study sought to evaluate the association of thoracic imaging findings with the renal mass characteristics in patients with pathologically proven renal cell carcinoma (RCC). Materials and Methods: We performed a retrospective analysis of patients with RCC, who underwent radical/partial nephrectomy and had baseline thoracic imaging available for review. Patients with a suspicious pulmonary mass were evaluated by the Department of Thoracic Surgery. Presence of lung nodule(s) and metastasis was determined and compared with patient and renal mass characteristics. Results: A total of 215 patients were included in the study. Pulmonary nodules suspicious for malignancy were present in 26.8% of the cases and 42% of these patients underwent further examination for the presence of a pulmonary mass. Pathological examination of the pulmonary nodule revealed RCC metastasis in 80% of patients who underwent biopsy or excision of the pulmonary nodule. Of note, in the subgroup analysis according to the pathological stage of the renal mass, 19.3% of patients with pT1a disease had a suspicious pulmonary mass on thoracic imaging. Of these patients, 25% underwent further examination of the pulmonary nodule with a RCC metastasis in 66.6%. Conclusion: The presence of suspicious lung nodules in patients with RCC has metastatic potential regardless of the size of the renal mass. These findings underscore the importance of baseline thoracic imaging and vigilant further evaluation of patients in whom pulmonary nodules are identified. [ABSTRACT FROM AUTHOR]

Purpose Lymphangioleiomyomatosis (LAM) is characterized by proliferation of smooth muscle tissue that causes bronchial obstruction and secondary cystic destruction of lung parenchyma. The aim of this study was to evaluate the typical distribution of cystic defects in LAM with quantitative volumetric chest computed tomography (CT). Materials and methods CT examinations of 20 patients with confirmed LAM were evaluated with region-based quantification of lung parenchyma. Additionally, 10 consecutive patients were identified who had recently undergone CT imaging of the lung at our institution, in which no pathologies of the lung were found, to serve as a control group. Each lung was divided into three regions (upper, middle and lower thirds) with identical number of slices. In addition, we defined a “peel” and “core” of the lung comprising the 2 cm subpleural space and the remaining inner lung area. Computerized detection of lung volume and relative emphysema was performed with the PULMO 3D software (v3.42, Fraunhofer MEVIS, Bremen, Germany). This software package enables the quantification of emphysematous lung parenchyma by calculating the pixel index, which is defined as the ratio of lung voxels with a density <−950 HU to the total number of voxels in the lung. Results Cystic changes accounted for 0.1–39.1% of the total lung volume in patients with LAM. Disease manifestation in the central lung was significantly higher than in peripheral areas (peel median: 15.1%, core median: 20.5%; p = 0.001). Lower thirds of lung parenchyma showed significantly less cystic changes than upper and middle lung areas combined (lower third: median 13.4, upper and middle thirds: median 19.0, p = 0.001). Conclusion The distribution of cystic lesions in LAM is significantly more pronounced in the central lung compared to peripheral areas. There is a significant predominance of cystic changes in apical and intermediate lung zones compared to the lung bases. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to evaluate the diagnostic performance of chest radiography (CXR), chest digital tomosynthesis (DT) and low dose multidetector computed tomography (LDCT) for the detection of small pulmonary ground-glass opacity (GGO) nodules, using an anthropomorphic chest phantom. Methods: Artificial pulmonary nodules were placed in a phantom and a total of 40 samples of different nodule settings underwent CXR, DT and LDCT. The images were randomly read by three experienced chest radiologists. Free-response receiver-operating characteristics (FROC) were used. Results: The figures of merit for the FROC curves averaged for the three observers were 0.41, 0.37 and 0.76 for CXR, DT and LDCT, respectively. FROC analyses revealed significantly better performance of LDCT over CXR or DT for the detection of GGO nodules ( P < 0.05). The difference in detectability between CXR and DT was not statistically significant ( P = 0.73). Conclusion: The diagnostic performance of DT for the detection of pulmonary small GGO nodules was not significantly different from that of CXR, but LDCT performed significantly better than both CXR and DT. DT is not a suitable alternative to CT for small GGO nodule detection, and LDCT remains the method of choice for this purpose. Key Points: • For GGO nodule detection, DT was not significantly different from CXR. • DT is not a suitable alternative to CT for GGO nodule detection. • LDCT is the method of choice for GGO nodule detection. [ABSTRACT FROM AUTHOR]

Computed tomography currently accounts for the majority of radiation exposure related to medical imaging. Although technological improvement of CT scanners has reduced the radiation dose of individual examinations, the benefit was overshadowed by the rapid increase in the number of CT examinations. Radiation exposure from CT examination should be kept as low as reasonably possible for patient safety. Measures to avoid inappropriate CT examinations are needed. Principles and information on radiation dose reduction in chest CT are reviewed in this article. The reduction of tube current and tube potential are the mainstays of dose reduction methods. Study results indicate that routine protocols with reduced tube current are feasible with diagnostic results comparable to conventional standard dose protocols. Tube current adjustment is facilitated by the advent of automatic tube current modulation systems by setting the appropriate image quality level for the purpose of the examination. Tube potential reduction is an effective method for CT pulmonary angiography. Tube potential reduction often requires higher tube current for satisfactory image quality, but may still contribute to significant radiation dose reduction. Use of lower tube potential also has considerable advantage for smaller patients. Improvement in image production, especially the introduction of iterative reconstruction methods, is expected to lower radiation dose significantly. Radiation dose reduction in CT is a multifaceted issue. Understanding these aspects leads to an optimal solution for various indications of chest CT. [ABSTRACT FROM AUTHOR]

We present a 3-month-old boy with a type IIA sling left pulmonary artery associated with imperforate anus and rectourethral fistula. Tracheobronchial abnormalities are demonstrated using multidetector CT with 3-D volume rendering of the airways. This case represents a novel variant of an already rare entity with an unusually high right upper lobe bronchus and no evidence of associated tracheobronchial stenosis. [ABSTRACT FROM AUTHOR]

Purpose: In this work, the authors present a novel magnetic resonance imaging reconstruction method to improve the quality of MR images in the presence of respiratory motion for real-time thoracic image-guided radiotherapy. Methods: This new reconstruction method is called dynamic keyhole and utilizes a library of previously acquired, peripheral k-space datasets from the same (or similar) respiratory state in conjunction with central k-space datasets acquired in real-time. Internal or external respiratory signals are utilized to sort, match, and combine the two separate peripheral and central k-space datasets with respect to respiratory displacement, thereby reducing acquisition time and improving image quality without respiratory-related artifacts. In this study, the dynamic keyhole, conventional keyhole, and zero-filling methods were compared to full k-space acquisition (ground truth) for 60 coronal datasets acquired from 15 healthy human subjects. Results: For the same image-quality difference from the ground-truth image, the dynamic keyhole method reused 79% of the prior peripheral phase-encoding lines, while the conventional keyhole reused 73% and zero-filling 63% (p-value < 0.0001), corresponding to faster acquisition speed of dynamic keyhole for real-time imaging applications. Conclusions: This study demonstrates that the dynamic keyhole method is a promising technique for clinical applications such as image-guided radiotherapy requiring real-time MR monitoring of the thoracic region. Based on the results from this study, the dynamic keyhole method could increase the temporal resolution by a factor of five compared with full k-space methods. [ABSTRACT FROM AUTHOR]

Lung parenchyma is challenging to image with proton MRI. The large air space results in ∼1/5th as many signal-generating protons compared to other organs. Air/tissue magnetic susceptibility differences lead to strong magnetic field gradients throughout the lungs and to broad frequency distributions, much broader than within other organs. Such distributions have been the subject of experimental and theoretical analyses which may reveal aspects of lung microarchitecture useful for diagnosis. Their most immediate relevance to current imaging practice is to cause rapid signal decays, commonly discussed in terms of short T2* values of 1 ms or lower at typical imaging field strengths. Herein we provide a brief review of previous studies describing and interpreting proton lung spectra. We then link these broad frequency distributions to rapid signal decays, though not necessarily the exponential decays generally used to define T2* values. We examine how these decays influence observed signal intensities and spatial mapping features associated with the most prominent torso imaging sequences, including spoiled gradient and spin echo sequences. Effects of imperfect refocusing pulses on the multiple echo signal decays in single shot fast spin echo (SSFSE) sequences and effects of broad frequency distributions on balanced steady state free precession (bSSFP) sequence signal intensities are also provided. The theoretical analyses are based on the concept of explicitly separating the effects of reversible and irreversible transverse relaxation processes, thus providing a somewhat novel and more general framework from which to estimate lung signal intensity behavior in modern imaging practice. © 2014 Wiley Periodicals, Inc. Concepts Magn Reson Part A 43A: 29-53, 2014. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Imaging of the lungs is part of the routine diagnostic workup of patients with endometrial cancer. The present study aimed to determine the incidence of lung metastases in patients with endometrial cancer and to evaluate the clinical relevance of preoperative chest imaging in this population. Methods: A retrospective cross-sectional study was performed in four regional and one university hospital in the southeastern part of the Netherlands. A total of 784 patients with epithelial endometrial cancer diagnosed between 2002 and 2010 in five hospitals were included. Patients were followed up for at least 1year. Results: Of 784 patients, 541 (69.0%) underwent thoracic imaging and 11 showed findings suspicious for metastases perioperatively or during the 1-year follow-up period. In eight patients, the thoracic metastases were related to their endometrial cancer, resulting in an overall incidence of 1.0% (8/784, 95% CI=0.3–1.7%). These eight patients had high-risk subtypes of endometrial cancer (serous, clear cell or poorly differentiated endometrioid), and the incidence was 4.1% (8/193, 95% CI=1.9–8.3%) for these subtypes. Lung metastases were not detected in any of the patients with low-risk subtypes of endometrial cancer (n =566) at the time of diagnosis (95% CI=0–0.8%). Conclusions: The probability of detecting thoracic metastases during the diagnostic workup of patients with endometrial cancer is low. The present data suggest that thoracic imaging could be omitted from the diagnostic workup of patients with low-risk endometrial cancer. [Copyright &y& Elsevier]

Purpose: Computed tomography (CT) imaging is the modality of choice for lung cancer diagnostics. With the increasing number of lung interventions on sublobar level in recent years, determining and visualizing pulmonary segments in CT images and, in oncological cases, reliable segment-related information about the location of tumors has become increasingly desirable. Computer-assisted identification of lung segments in CT images is subject of this work. Methods: The authors present a new interactive approach for the segmentation of lung segments that uses the Euclidean distance of each point in the lung to the segmental branches of the pulmonary artery. The aim is to analyze the potential of the method. Detailed manual pulmonary artery segmentations are used to achieve the best possible segment approximation results. A detailed description of the method and its evaluation on 11 CT scans from clinical routine are given. Results: An accuracy of 2-3 mm is measured for the segment boundaries computed by the pulmonary artery-based method. On average, maximum deviations of 8 mm are observed. 135 intersegmental pulmonary veins detected in the 11 test CT scans serve as reference data. Furthermore, a comparison of the presented pulmonary artery-based approach to a similar approach that uses the Euclidean distance to the segmental branches of the bronchial tree is presented. It shows a significantly higher accuracy for the pulmonary artery-based approach in lung regions at least 30 mm distal to the lung hilum. Conclusions: A pulmonary artery-based determination of lung segments in CT images is promising. In the tests, the pulmonary artery-based determination has been shown to be superior to the bronchial tree-based determination. The suitability of the segment approximation method for application in the planning of segment resections in clinical practice has already been verified in experimental cases. However, automation of the method accompanied by an evaluation on a larger number of test cases is required before application in the daily clinical routine. [ABSTRACT FROM AUTHOR]

Abstract: Central-chest lymph nodes play a vital role in lung-cancer staging. The definition of lymph nodes from three-dimensional (3D) multidetector computed-tomography (MDCT) images, however, remains an open problem. We propose two methods for computer-based segmentation of the central-chest lymph nodes from a 3D MDCT scan: the single-section live wire and the single-click live wire. For the single-section live wire, the user first applies the standard live wire to a single two-dimensional (2D) section after which automated analysis completes the segmentation process. The single-click live wire is similar but is almost completely automatic. Ground-truth studies involving human 3D MDCT scans demonstrate the robustness, efficiency, and intra-observer and inter-observer reproducibility of the methods. [Copyright &y& Elsevier]

Simple Summary: Dogs diagnosed with bacterial pneumonia are often treated with long courses of antibiotics (3–6 weeks) and chest X-rays are used to help guide the duration of treatment. This is in stark contrast with humans with the same disease who are often treated for 5–10 days, and chest X-rays are not considered to be useful for monitoring response to treatment. The main goal of this study was to determine whether a shorter course of antibiotics (10 days) would be sufficient to treat dogs with bacterial pneumonia. Eight dogs with pneumonia were randomly assigned to receive 10 or 21 days of antibiotics. They were evaluated at 10, 30 and 60 days after diagnosis. At 10 days, 6/8 dogs had resolution of both clinical signs and evidence of inflammation on bloodwork and 5/8 dogs showed improvement in the chest X-rays. After 60 days, none of the dogs had clinical signs or evidence of inflammation on bloodwork regardless of antibiotic therapy duration. However, 3/8 dogs showed changes in the chest X-rays. This study suggests that a 10-day course of antibiotics may be sufficient to treat dogs with bacterial pneumonia, and chest X-rays may not be a reliable marker to monitor response to therapy. Current treatment for canine bacterial pneumonia relies on protracted courses of antimicrobials (3–6 weeks or more) with recommendations to continue for 1–2 weeks past resolution of all clinical and thoracic radiographic abnormalities. However, in humans, bacterial pneumonia is often treated with 5–10-day courses of antimicrobials, and thoracic radiographs are not considered useful to guide therapeutic duration. The primary study objective was to determine whether a short course of antimicrobials would be sufficient to treat canine bacterial pneumonia. Eight dogs with uncomplicated bacterial pneumonia were enrolled in this randomized, double-blinded, placebo-controlled study comparing clinical and radiographic resolution with differing durations of antimicrobial therapy. Dogs received a course of antimicrobials lasting 10 (A10) or 21 (A21) days. Dogs randomized to the A10 group received placebo for 11 days following antimicrobial therapy. Patients were evaluated at presentation and 10, 30 and 60 days after the initiation of antimicrobials. At 10 days, 6/8 dogs had resolution of both clinical signs and inflammatory leukogram, and 5/8 dogs had improved global radiographic scores. After 60 days, clinical and hematologic resolution of pneumonia was noted in all dogs regardless of antimicrobial therapy duration; however, 3/8 dogs had persistent radiographic lesions. Thoracic radiographs do not appear to be a reliable marker to guide antimicrobial therapy in canine bacterial pneumonia as radiographic lesions may lag or persist despite clinical cure. This pilot study suggests a 10-day course of antimicrobials may be sufficient to treat uncomplicated canine bacterial pneumonia. [ABSTRACT FROM AUTHOR]

Experiments were conducted to determine optimal acquisition techniques for bone image decompositions for a prototype dual-energy (DE) imaging system. Technique parameters included kVp pair (denoted [kVpL/kVpH]) and dose allocation (the proportion of dose in low- and high-energy projections), each optimized to provide maximum signal difference-to-noise ratio in DE images. Experiments involved a chest phantom representing an average patient size and containing simulated ribs and lung nodules. Low- and high-energy kVp were varied from 60–90 and 120–150 kVp, respectively. The optimal kVp pair was determined to be [60/130] kVp, with image quality showing a strong dependence on low-kVp selection. Optimal dose allocation was approximately 0.5—i.e., an equal dose imparted by the low- and high-energy projections. The results complement earlier studies of optimal DE soft-tissue image acquisition, with differences attributed to the specific imaging task. Together, the results help to guide the development and implementation of high-performance DE imaging systems, with applications including lung nodule detection and diagnosis, pneumothorax identification, and musculoskeletal imaging (e.g., discrimination of rib fractures from metastasis). [ABSTRACT FROM AUTHOR]

Experimental and theoretical studies were conducted to determine optimal acquisition techniques for a prototype dual-energy (DE) chest imaging system. Technique factors investigated included the selection of added x-ray filtration, kVp pair, and the allocation of dose between low- and high-energy projections, with total dose equal to or less than that of a conventional chest radiograph. Optima were computed to maximize lung nodule detectability as characterized by the signal-difference-to-noise ratio (SDNR) in DE chest images. Optimal beam filtration was determined by cascaded systems analysis of DE image SDNR for filter selections across the periodic table (Zfilter=1–92), demonstrating the importance of differential filtration between low- and high-kVp projections and suggesting optimal high-kVp filters in the range Zfilter=25–50. For example, added filtration of ∼2.1 mm Cu, ∼1.2 mm Zr, ∼0.7 mm Mo, and ∼0.6 mm Ag to the high-kVp beam provided optimal (and nearly equivalent) soft-tissue SDNR. Optimal kVp pair and dose allocation were investigated using a chest phantom presenting simulated lung nodules and ribs for thin, average, and thick body habitus. Low- and high-energy techniques ranged from 60–90 kVp and 120–150 kVp, respectively, with peak soft-tissue SDNR achieved at [60/120] kVp for all patient thicknesses and all levels of imaging dose. A strong dependence on the kVp of the low-energy projection was observed. Optimal allocation of dose between low- and high-energy projections was such that ∼30% of the total dose was delivered by the low-kVp projection, exhibiting a fairly weak dependence on kVp pair and dose. The results have guided the implementation of a prototype DE imaging system for imaging trials in early-stage lung nodule detection and diagnosis. [ABSTRACT FROM AUTHOR]

Sonography (US) has inherent limitations for thoracic imaging because sound waves are reflected by bone and air space (such as in lung parenchyma). However, US is less expensive and more convenient than computed tomography (CT) or magnetic resonance imaging (MRI); it provides immediate information with real-time imaging, and can give information not available from a standard radiograph. This review describes the utility and limitations of US and compares US with radiography. [ABSTRACT FROM AUTHOR]

Background: The outbreak of COVID-19 has become pandemic. Pediatric population has been less studied than adult population and prompt diagnosis is challenging due to asymptomatic or mild episodes. Radiology is an important complement to clinical and epidemiological features.Objective: To establish the most common CXR patterns in children with COVID-19, evaluate interobserver correlation and to discuss the role of imaging techniques in the management of children.Materials and Methods: Forty-four patients between 0 and 16 years of age with confirmed SARS-Cov-2 infection and CXR were selected. Two paediatric radiologists independently evaluated the images and assessed the type of abnormality, distribution and evolution when available.Results: Median age was 79.8 months (ranging from 2 weeks to 16 years of age). Fever was the most common symptom (43.5 %). 90 % of CXR showed abnormalities. Peribronchial cuffing was the most common finding (86.3 %) followed by GGOs (50 %). In both cases central distribution was more common than peripheral. Consolidations accounted for 18.1 %. Normal CXR, pleural effusion, and altered cardiomediastinal contour were the least common.Conclusion: The vast majority of CXR showed abnormalities in children with COVID-19. However, findings are nonspecific. Interobserver correlation was good in describing consolidations, normal x-rays and GGOs. Imaging techniques have a role in the management of children with known or suspected COVID-19, especially in those with moderate or severe symptoms or with underlying risk factors. [ABSTRACT FROM AUTHOR]

Negative pressure pulmonary edema (NPPE) is a rare, potentially life-threatening, and yet diagnostically challenging perioperative complication. Most cases of NPPE occur in the context of anesthetic procedures, mainly caused by upper airway obstruction, and are diagnosed during the recovery period. We present a case of fulminant NPPE in a patient during general anesthesia which illustrates the eye-catching CT findings that can occur in NPPE and eventually support diagnosis. With regard to the current pandemic, we include a discussion of the typical imaging patterns of COVID-19 as a radiological differential diagnosis of NPPE. A 42-year old male patient presented with sudden respiratory insufficiency during arthroscopic knee lavage and subsequently required highly invasive ventilation therapy and catecholamine administration. Postoperative CT imaging of the thorax exhibited extensive, centrally accentuated consolidations with surrounding ground-glass opacity in all lung lobes, suggestive of pulmonary edema. In view of the clinical course and the imaging findings, a negative pressure pulmonary edema (NPPE) was diagnosed. [ABSTRACT FROM AUTHOR]

The thoracic inlet is located at the crossroads between imaging of the neck and the chest. Its location is an important anatomic landmark, serving as the central conducting pathway for many vital structures extending from the neck into the chest and vice versa. Many critical body systems, including the respiratory, lymphatic, neurologic, enteric, musculoskeletal, endocrine, and vascular systems, are located within this region. Neoplasms, both benign and malignant, can arise in any of the body systems located in this area. Due to the small size of this anatomic location, pathology is easily overlooked and imagers should be aware of the imaging appearance of these neoplasms, as well as which imaging modality is the most appropriate for neoplasm evaluation. This article will present an image rich, system-based discussion of the neoplastic pathology that can occur in this region. The anatomy of the thoracic inlet and the non-neoplastic pathology of the thoracic inlet have been covered in our companion article. [ABSTRACT FROM AUTHOR]

Artificial intelligence is a hot topic in medical imaging. The development of deep learning methods and in particular the use of convolutional neural networks (CNNs), have led to substantial performance gain over the classic machine learning techniques. Multiple usages are currently being evaluated, especially for thoracic imaging, such as such as lung nodule evaluation, tuberculosis or pneumonia detection or quantification of diffuse lung diseases. Chest radiography is a near perfect domain for the development of deep learning algorithms for automatic interpretation, requiring large annotated datasets, in view of the high number of procedures and increasing data availability. Current algorithms are able to detect up to 14 common anomalies, when present as isolated findings. Chest computed tomography is another major field of application for artificial intelligence, especially in the perspective of large scale lung cancer screening. It is important for radiologists to apprehend, contribute actively and lead this new era of radiology powered by artificial intelligence. Such a perspective requires understanding new terms and concepts associated with machine learning. The objective of this paper is to provide useful definitions for understanding the methods used and their possibilities, and report current and future developments for thoracic imaging. Prospective validation of AI tools will be required before reaching routine clinical implementation. [ABSTRACT FROM AUTHOR]

Accessory cardiac bronchus is a poorly recognized, usually asymptomatic, congenital abnormality of the bronchial tree. Recognition of bronchial anomalies is important since they are associated with clinical complications including recurrent episodes of infection, hemoptysis, and in some cases malignancy. [ABSTRACT FROM AUTHOR]