Contrast-Enhanced Ultrasound of the Chest in Children and Adolescents: A Pilot Study for Assessment of Added Diagnostic Value.

OBJECTIVES: To determine the added diagnostic value of contrast-enhanced ultrasound (CEUS) in pediatric chest abnormalities by comparing interpretation of CEUS studies and confidence level to conventional US studies. METHODS: CEUS studies in patients with a variety of clinically suspected chest abnormalities performed between 2016 and 2020 were reviewed and compared to same-day conventional US studies. Examinations were independently interpreted by 4 radiologists blinded to clinical and other imaging data. Rater confidence was classified as low, moderate, or high. Diagnostic accuracy was determined by comparing image interpretation to patient outcome as the ground truth. Interobserver agreement was also assessed. RESULTS: Sixteen patients (10 male) with 18 CEUS studies were included. Median rater agreement with ground truth was significantly higher for CEUS (100%) than conventional US (50%; P = .004). Median rater confidence was high (3.0) for CEUS, and low-moderate (1.5) for conventional US (P < .001). CEUS sensitivity (54.6-81.8%) and specificity (63.4-100.0%) were greater than conventional US (45.5-72.7% and 12.5-63.5%, respectively). CEUS false positives (0-4) and false negatives (2-5) were fewer than conventional US (4-7 and 3-6, respectively). Except for one rater pair where agreement was substantial (κ = .78, P < .01), inter-rater agreement for CEUS for all other rater pairs was nonsignificant (κ = .25-0.51, P ≥ .07). Agreement for conventional US was moderate and statistically significant for 3 rater pairs (κ = .55-0.78) and nonsignificant for the remaining 3 rater pairs (P ≥ .06). CONCLUSIONS: CEUS adds diagnostic value to the assessment of a variety of chest abnormalities. The data support further evaluation of the role of CEUS as a non-invasive, problem-solving technique in children.

Unusual pediatric lung infections: imaging findings.

Pediatric lung infections continue to be a leading cause of pediatric morbidity and mortality. Although both pediatric and general radiologists are familiar with typical lung infections and their imaging findings in children, relatively rare lung infections continue to present a diagnostic challenge. In addition, the advances in radiological imaging and emergence of several new lung infections in recent years facilitated the need for up-to-date knowledge on this topic. In this review article, we discuss the imaging findings of pediatric lung infections caused by unusual/uncommon and new pathogens. We review the epidemiological, clinical, and radiological imaging findings of viral (coronavirus disease 2019, Middle East respiratory syndrome, bird flu), bacterial (Streptococcus anginosus, Francisella tularensis, Chlamydia psittaci), and parasitic lung infections (echinococcosis, paragonimiasis, amoebiasis). Additional disorders whose clinical course and imaging findings may mimic lung infections in children (hypersensitivity pneumonitis, pulmonary hemorrhage, eosinophilic pneumonia) are also presented, to aid in differential diagnosis. As the clinical presentation of children with new and unusual lung infections is often non-specific, imaging evaluation plays an important role in initial detection, follow-up for disease progression, and assessment of potential complications.

Ultrasound-guided hydrostatic reduction of intussusception: comparison of success rates between subspecialized pediatric radiologists and non-pediatric radiologists or radiology residents.

Ileocolic intussusception is the most common cause of intestinal obstruction in children under two years of age. Treatment in most cases is radiologically guided reduction. In Slovenia, ultrasound (US)-guided hydrostatic reduction is currently the standard of care. The purpose of this study was to compare the success rate of US-guided hydrostatic reduction when performed by subspecialty-trained pediatric radiologists, non-pediatric radiologists, or radiology residents. We retrospectively analyzed medical records of patients with ileocolic intussusception who underwent US-guided hydrostatic intussusception reduction at University Medical Centre Ljubljana between January 2012 and December 2022 (n = 101). During regular daily working hours, the reduction was performed by pediatric radiologists. After hours (evenings and overnight), pediatric radiologists, non-pediatric radiologists, or radiology residents performed the reduction procedure. Patients were divided into three groups based on the operator performing the procedure. Data was analyzed using the chi-square test. Pediatric radiologists had thirty-seven (75.5%) successful first attempts, non-pediatric radiologists had nineteen (76.0%), and radiology residents had twenty (74.1%). There was no statistically significant difference in the success rate of ileocolic intussusception reduction depending on the operator who performed the procedure (p = 0.98). No perforation was observed in either group during the reduction attempts.  Conclusion: Our results demonstrate that US-guided hydrostatic reduction is a reliable and safe procedure that achieves good results even in the hands of less experienced, however appropriately trained, radiologists. The results should encourage more medical centers to consider the implementation of US-guided hydrostatic reduction of ileocolic intussusception. What is Known: • US-guided hydrostatic reduction is a well-established method of treatment for ileocolic intussusception in children. • The results regarding the influence of operator's experience with the procedure on its success rate are scarce and contradictory. What is New: • US-guided hydrostatic intussusception reduction is a reliable and safe technique that achieves similar success rates when performed by experienced subspecialized pediatric radiologists or less experienced but trained operators such as non-pediatric radiologists and radiology residents. • The implementation of US-guided hydrostatic reduction in general hospitals without subspecialized pediatric radiologists could improve patient care by increasing access to radiologically guided reduction and simultaneously decreasing the time to reduction attempts.

Computed tomography and magnetic resonance imaging for pulmonary embolus evaluation in children: up-to-date review on practical imaging protocols.

Pulmonary embolism (PE) is a potentially life-threatening condition that requires immediate medical intervention. Although PE was previously thought to occur infrequently in the pediatric population, recent studies have found a higher-than-expected prevalence of PE in the pediatric population of up to 15.5%. The imaging modality of choice for detecting PE in the pediatric population is multi-detector CT angiography, although MRI is assuming a growing and more important role as a potential alternative modality. Given the recent advances in both computed tomography pulmonary angiography (CTPA) and MRI techniques, a growing population of pediatric patients with complex comorbidities (such as children with a history of surgeries for congenital heart disease repair), and the recent waves of coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome in children (MIS-C), which are associated with increased risk of PE, there is new and increased need for an up-to-date review of practical CT and MRI protocols for PE evaluation in children. This article provides guidance for up-to-date CT and MR imaging techniques, reviews key recent studies on the imaging of pediatric PE, and discusses relevant pediatric PE imaging pearls and pitfalls, in hopes of providing readers with up-to-date and accurate practice for imaging evaluation of PE in children.

Tuberculosis revisted: classic imaging findings in childhood.

Tuberculosis (TB) remains one of the major public health threats worldwide, despite improved diagnostic and therapeutic methods. Tuberculosis is one of the main causes of infectious disease in the chest and is associated with substantial morbidity and mortality in paediatric populations, particularly in low- and middle-income countries. Due to the difficulty in obtaining microbiological confirmation of pulmonary TB in children, diagnosis often relies on a combination of clinical and radiological findings. The early diagnosis of central nervous system TB is challenging with presumptive diagnosis heavily reliant on imaging. Brain infection can present as a diffuse exudative basal leptomeningitis or as localised disease (tuberculoma, abscess, cerebritis). Spinal TB may present as radiculomyelitis, spinal tuberculoma or abscess or epidural phlegmon. Musculoskeletal manifestation accounts for 10% of extrapulmonary presentations but is easily overlooked with its insidious clinical course and non-specific imaging findings. Common musculoskeletal manifestations of TB include spondylitis, arthritis and osteomyelitis, while tenosynovitis and bursitis are less common. Abdominal TB presents with a triad of pain, fever and weight loss. Abdominal TB may occur in various forms, as tuberculous lymphadenopathy or peritoneal, gastrointestinal or visceral TB. Chest radiographs should be performed, as approximately 15% to 25% of children with abdominal TB have concomitant pulmonary infection. Urogenital TB is rare in children. This article will review the classic radiological findings in childhood TB in each of the major systems in order of clinical prevalence, namely chest, central nervous system, spine, musculoskeletal, abdomen and genitourinary system.

Lung and large airway imaging: magnetic resonance imaging versus computed tomography.

Disorders of the respiratory system are common in children and imaging plays an important role for initial diagnosis and follow-up evaluation. Radiographs are typically the first-line imaging test for respiratory symptoms in children and, when advanced imaging is required, CT has been the most frequently used imaging modality. However, because of increasing concern about potentially harmful effects of ionizing radiation on children, there has been a shift toward MRI in pediatric imaging. Although MRI of chest in children presents many technical challenges, recent advances in MRI technology are overcoming many of these issues, and MRI is now being used for evaluating the lung and large airway in children at centers with expertise in pediatric chest MRI. In this article we review the state of pediatric lung and large airway imaging, with an emphasis on cross-sectional modalities and the roles of MRI versus CT.

Pediatric large airway imaging: evolution and revolution.

Infants and children often present with respiratory symptoms referable to the airway. For these pediatric patients, airway imaging is frequently performed to evaluate for underlying disorders of the large airway. Various imaging modalities have been used to evaluate the pediatric large airway, and pediatric airway imaging techniques have continued to evolve. Therefore, clear understanding of the status and new advances in pediatric large airway imaging is essential for practicing radiologists to make timely and accurate diagnoses, which can lead to optimal pediatric patient management.

Imaging evaluation of the pediatric mediastinum: new International Thymic Malignancy Interest Group classification system for children.

Mediastinal masses are commonly identified in the pediatric population with cross-sectional imaging central to the diagnosis and management of these lesions. With greater anatomical definition afforded by cross-sectional imaging, classification of mediastinal masses into the traditional anterior, middle and posterior mediastinal compartments - as based on the lateral chest radiograph - has diminishing application. In recent years, the International Thymic Malignancy Interest Group (ITMIG) classification system of mediastinal masses, which is cross-sectionally based, has garnered acceptance by multiple thoracic societies and been applied in adults. Therefore, there is a need for pediatric radiologists to clearly understand the ITMIG classification system and how it applies to the pediatric population. The main purpose of this article is to provide an updated review of common pediatric mediastinal masses and mediastinal manifestations of systemic disease processes in the pediatric population based on the new ITMIG classification system.

CT Features of Benign Intrapulmonary Lymph Nodes in Pediatric Patients With Known Extrapulmonary Solid Malignancy.

OBJECTIVE. The purpose of our study was to determine the CT features of benign intrapulmonary lymph nodes in pediatric patients with known extrapulmonary solid malignancy. MATERIALS AND METHODS. A retrospective review of surgical pathology archives was performed to identify consecutive chest CT studies of pediatric patients (≤ 18 years) with extrapulmonary solid malignancy and histologically confirmed benign intrapulmonary lymph nodes between January 1, 2004, and March 15, 2020. CT features of intrapulmonary lymph nodes-including size, shape, margin, type, associated calcification or fat, and location-were independently evaluated by two pediatric radiologist reviewers. The CT features of benign intrapulmonary lymph nodes in pediatric patients were analyzed using summary statistics. Interobserver agreement was measured with the kappa coefficient. RESULTS. There were 36 pathology-confirmed benign intrapulmonary lymph nodes in 27 pediatric patients (18 boys and nine girls; mean age, 12 years; age range, 1-18.2 years). Twenty-three (63.9%) of the benign intrapulmonary lymph nodes were biopsied from the right lung and 13 (36.1%) from the left lung (p = .03). The mean size, determined from CT studies, of benign intrapulmonary lymph nodes was 3.6 mm (SD, 1.4 mm; range, 1.3-7.8 mm). Triangular shape (25/36, 69.4%) was the most common shape of the benign intrapulmonary lymph nodes. Less commonly seen shapes of benign intrapulmonary lymph nodes were oval (6/36, 16.7%), round (3/36, 8.3%), and trapezoidal (2/36, 5.6%). All benign intrapulmonary lymph nodes were smoothly marginated and solid without associated calcification or fat. Of the 36 benign intrapulmonary lymph nodes, 15 (41.7%) were pleura-based; 11 (30.6%), perifissural; and 10 (27.8%), parenchymal. The kappa value for interobserver agreement between the two reviewers was 0.917 (95% CI, 0.825-1.000; standard error, 0.047), which corresponds to near-perfect agreement. CONCLUSION. In pediatric patients with known extrapulmonary solid malignancy, benign intrapulmonary lymph nodes are subcentimeter (mean size, 3.6 mm), smoothly marginated, and solid without containing calcification or fat on CT. In particular, triangular shape was the most commonly encountered shape of a benign intrapulmonary lymph node.

Pediatric Chest Radiographic and CT Findings of Electronic Cigarette or Vaping Product Use-associated Lung Injury (EVALI).

Background Electronic cigarette or vaping product use-associated lung injury (EVALI) is a serious public health concern with substantial morbidity and mortality, particularly in young individuals. Purpose To evaluate chest radiographic and chest CT findings of EVALI in the pediatric population. Materials and Methods This was a retrospective study of children who presented to a tertiary pediatric hospital from December 2018 to December 2019. Patients fulfilled the Centers for Disease Control and Prevention criteria for EVALI and had chest radiographs and CT images available at initial presentation. Two pediatric radiologists independently reviewed imaging for pattern, distribution, and extent of pulmonary abnormalities, as well as for extrapulmonary abnormalities. Clinical information, management, and outcomes were reviewed. Interobserver agreement was measured with Cohen κ coefficient. Results Seven male patients (50%) and seven female patients (50%) (mean age, 16 years; range, 13-18 years) were evaluated. All patients underwent chest radiography and CT within 4 days of presentation (range, 0-4 days). Chest radiographic findings included ground-glass opacity in 14 of 14 (100%) and consolidation in eight of 14 (57%). CT findings included ground-glass opacity in 14 of 14 (100%), consolidation in nine of 14 (64%), and interlobular septal thickening in two of 14 (14%). At CT, subpleural sparing was seen in 11 of 14 (79%) and a reversed halo sign was seen in five of 14 (36%). Chest radiographic and CT abnormalities were predominately bilateral in 14 of 14 (100%) and symmetric in 13 of 14 (93%), with lower lobe predominance in seven of 14 (50%). Extent of abnormality was predominately diffuse at both chest radiography and CT. There was almost perfect interobserver agreement between two reviewers for detecting abnormalities on chest radiographs (κ = 0.99; 95% confidence interval: 0.97, 1.00) and CT (κ = 0.99; 95% confidence interval: 0.98, 1.00). Conclusion In pediatric patients, electronic cigarette or vaping product use-associated lung injury is characterized by bilateral symmetric ground-glass opacities, consolidation, and a lower lobe predominance at CT. © RSNA, 2020.

Pediatric SARS, H1N1, MERS, EVALI, and Now Coronavirus Disease (COVID-19) Pneumonia: What Radiologists Need to Know.

OBJECTIVE. The purpose of this article is to review new pediatric lung disorders-including disorders that have occurred in recent years years such as severe acute respiratory syndrome (SARS), swine-origin influenza A (H1N1), Middle East respiratory syndrome (MERS), e-cigarette or vaping product use-associated lung injury (EVALI), and coronavirus disease (COVID-19) pneumonia-to enhance understanding of the characteristic imaging findings. CONCLUSION. Although the clinical symptoms of SARS, H1N1, MERS, EVALI, and COVID-19 pneumonia in pediatric patients may be nonspecific, some characteristic imaging findings have emerged or are currently emerging. It is essential for radiologists to have a clear understanding of the characteristic imaging appearances of these lung disorders in pediatric patients to ensure optimal patient care.

Imaging and clinicopathologic features of esophageal gastrointestinal stromal tumors.

OBJECTIVE: The purpose of this article is to describe the imaging and clinicopathologic characteristics of esophageal gastrointestinal stromal tumors (GISTs) and to emphasize the features that differentiate esophageal GISTs from esophageal leiomyomas. MATERIALS AND METHODS: A pathology database search identified all surgically resected or biopsied esophageal GISTs, esophageal leiomyomas, and esophageal leiomyosarcomas from 1994 to 2012. Esophageal GISTs were included only if imaging studies (including CT, fluoroscopic, or (18)F-FDG PET/CT scans) and clinical data were available. RESULTS: Nineteen esophageal mesenchymal tumors were identified, including eight esophageal GISTs (42%), 10 esophageal leiomyomas (53%), and one esophageal leiomyosarcoma (5%). Four patients (50%) with esophageal GIST had symptoms, including dysphagia in three (38%), cough in one (13%), and chest pain in one (13%). One esophageal GIST appeared on barium study as a smooth submucosal mass. All esophageal GISTs appeared on CT as well-marginated predominantly distal lesions, isoattenuating to muscle, that moderately enhanced after IV contrast agent administration. Compared with esophageal leiomyomas, esophageal GISTs tended to be more distal, larger, and more heterogeneous and showed greater IV enhancement on CT. All esophageal GISTs showed marked avidity (mean maximum standardized uptake value, 16) on PET scans. All esophageal GISTs were positive for c-KIT (a cell-surface transmembrane tyrosine kinase also known as CD117) and CD34. On histopathology, six esophageal GISTs (75%) were of the spindle pattern and two (25%) were of a mixed spindle and epithelioid pattern. Five esophageal GISTs had exon 11 mutations (with imatinib sensitivity). Clinical outcome correlated with treatment strategy (resection plus adjuvant therapy or resection alone) rather than risk stratification. CONCLUSION: Esophageal GISTs are unusual but clinically important mesenchymal neoplasms. Although esophageal GISTs and esophageal leiomyomas had overlapping imaging features, esophageal GISTs tended to be more distal, larger, more heterogeneous, and more enhancing on CT and were markedly FDG avid on PET. Given their malignant potential, esophageal GISTs should be included in the differential diagnosis of intramural esophageal neoplasms.

More than just metastases: a practical approach to solid mesenteric masses.

The abdominal mesenteries are important peritoneal structures that give rise to a wide spectrum of abnormalities, including solid mesenteric masses. Despite similarities in appearance, solid masses in the mesentery may have diverse etiologies, ranging from benign to highly malignant. While metastases are the most common cause of solid masses in the mesentery, other less common conditions are also important diagnostic considerations. This article reviews four pathologic entities (sclerosing mesenteritis, carcinoid tumors, desmoids tumors, and gastrointestinal stromal tumors) that may be manifested on abdominal imaging examinations by one or more mesenteric masses. These four pathologic entities are used to present a systematic approach to the radiographic characterization of solid mesenteric masses based on the morphology of the lesions, locoregional effects, and distant findings on various abdominal imaging examinations.

Magnetic Resonance Imaging of Pediatric Lungs and Airways: New Paradigm for Practical Daily Clinical Use.

Disorders of the lungs and airways are among the most common indications for diagnostic imaging in infants and children. Traditionally, chest radiograph has been the first-line imaging test for detecting these disorders and when cross-sectional imaging is necessary, computed tomography (CT) has typically been the next step. However, due to concerns about the potentially harmful effects of ionizing radiation, pediatric imaging in general has begun to shift away from CT toward magnetic resonance imaging (MRI) as a preferred modality. Several unique technical challenges of chest MRI, including motion artifact from respiratory and cardiac motion as well as low signal-to-noise ratios secondary to relatively low proton density in the lung have slowed this shift in thoracic imaging. However, technical advances in MRI in recent years, including developments in non-Cartesian MRI data sampling methods such as radial, spiral, and PROPELLER imaging and the development of ultrashort TE and zero TE sequences that render CT-like high-quality imaging with minimal motion artifact have allowed for a shift to MRI for evaluation of lung and large airways in centers with specialized expertise. This article presents a practical approach for radiologists in current practice to begin to consider MRI for evaluation of the pediatric lung and large airways and begin to implement it in their practices. The current role for MRI in the evaluation of disorders of the pediatric lung and large airways is reviewed, and example cases are presented. Challenges for MRI of the lung and large airways in children are discussed, practical tips for patient preparation including sedation are described, and imaging techniques suitable for current clinical practice are presented.

Neonatal and Infant Lung Disorders: Glossary, Practical Approach, and Diagnoses.

A multitude of lung disorders ranging from congenital and genetic anomalies to iatrogenic complications can affect the neonate or the infant within the first year of life. Neonatal and infant chest imaging, predominantly by plain radiography and computed tomography, is frequently employed to aid in diagnosis and management; however, these disorders can be challenging to differentiate due to their broad-ranging, and frequently overlapping radiographic features. A systematic and practical approach to imaging interpretation which includes recognition of radiologic patterns, utilization of commonly accepted nomenclature and classification, as well as interpretation of imaging findings in conjunction with clinical history can not only assist radiologists to suggest the diagnosis, but also aid clinicians in management planning. The contents of this article were endorsed by the leadership of both the World Federation of Pediatric Imaging (WFPI), and the International Society of Pediatric Thoracic Imaging (ISPTI).

Necessity of Routine Chest Radiograph Following Chest Tube Removal in Pediatric Patients After Cardiovascular Surgery.

PURPOSE: Chest tube placement and subsequent removal is a routine step in patient management after cardiovascular surgery. The purpose of this retrospective study is to determine the necessity of routine chest radiography following chest tube removal in order to detect potential complications in pediatric patients after cardiovascular surgery. MATERIALS AND METHODS: We retrospectively reviewed the hospital records of all consecutive children up to 5 years of age who had cardiovascular surgery at our hospital between January 2015 and December 2020. Two radiologists independently evaluated routine chest radiographs performed 4 hours following chest tube removal for the presence of potential complications. In all post chest tube removal chest radiographs that demonstrated a complication, the patient's medical record was investigated in order to determine if there was an associated clinical or laboratory test abnormality, and if the radiographically detected complication led to a change in patient management. Inter-rater agreement between the 2 reviewers was evaluated with κ statistics. RESULTS: We identified 147 children (73 [49.7%] male and 74 [50.3%] female; mean age=13.8 mo old; range 0 to 60 mo) who met the inclusion criteria. Complications were detected on routine chest radiograph after chest tube removal in 10 patients (6.8%) including pneumothorax (n=5, 3.4%), pleural effusion (n=3, 2%), pneumomediastinum (n=1, 0.7%), and pneumopericardium (n=1, 0.7%). No clinical or laboratory abnormalities were present in all children affected with radiographically detected complications on routine chest radiograph 4 hours after chest tube removal, and there was no need for intervention in any affected patients. There was high inter-rater κ agreement between the 2 independent reviewers for detecting complications on chest radiographs after chest tube removal (κ=0.94). CONCLUSION: Our study shows that routine chest radiograph performed shortly after chest tube removal may not be necessary for the safe management of asymptomatic children after cardiovascular surgery because complications are rare and do not require intervention. In addition, obviating performance of this routine chest radiograph following chest tube removal will lead to a substantial decrease in exposure to unnecessary ionizing radiation in children who undergo frequent radiographs and lower medical costs.

Pediatric Pulmonary Embolism: Imaging Guidelines and Recommendations.

In contrast with the algorithms and screening criteria available for adults with suspected pulmonary embolism, there is a paucity of guidance on the diagnostic approach for children. The incidence of pulmonary embolism in the pediatric population and young adults is higher than thought, and there is an urgent need for updated guidelines for the imaging approach to diagnosis in the pediatric population. This article presents an up-to-date review of imaging techniques, characteristic radiologic findings, and an evidence-based algorithm for the detection of pediatric pulmonary embolism to improve the care of pediatric patients with suspected pulmonary embolism.

Childhood Interstitial Lung Disease: Imaging Guidelines and Recommendations.

Childhood interstitial lung disease (ChILD) is an umbrella term encompassing a diverse group of diffuse lung diseases affecting infants and children. Although the timely and accurate diagnosis of ChILD is often challenging, it is optimally achieved through the multidisciplinary integration of imaging findings with clinical data, genetics, and potentially lung biopsy. This article reviews the definition and classification of ChILD; the role of imaging, pathology, and genetics in ChILD diagnosis; treatment options; and future goals. In addition, a practical approach to ChILD imaging based on the latest available research and the characteristic imaging appearance of ChILD entities are presented.

Pediatric Congenital Lung Malformations: Imaging Guidelines and Recommendations.

Congenital lung malformations are a spectrum of developmental anomalies comprised of malformations of the lung parenchyma, airways, and vasculature. Imaging assessment plays a pivotal role in the initial diagnosis, management, and follow-up evaluation of congenital lung malformations in the pediatric population. However, there is currently a lack of practical imaging guidelines and recommendations for the diagnostic imaging assessment of congenital lung malformations in infants and children. This article reviews the current evidence regarding the imaging evaluation of congenital lung malformations and provides up-to-date imaging recommendations for pediatric congenital lung malformations.