Respiratory Failure Due to Idiopathic Pneumonia Syndrome in a Pediatric Patient After Recipient-derived Allogeneic Chimeric Antigen Receptor T-Cell Therapy.

Idiopathic pneumonia syndrome (IPS) is a life-threatening complication of hematopoietic cell transplantation, but it is not clearly described following chimeric antigen receptor (CAR) T-cell therapy. We describe a child who developed IPS after receiving tisagenlecleucel for post-hematopoietic cell transplantation relapsed acute lymphoblastic leukemia and had a remarkable improvement after treatment with corticosteroids and etanercept. We discuss the implications of cytokine signaling in IPS and immunologic considerations of allogeneic CAR T cells. We anticipate that the incidence of IPS and other allogeneic phenomena will be observed more often as allogeneic CAR T cells are employed in more varied settings with more mismatched donors.

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 findings in acute pediatric coronavirus disease 2019 (COVID-19) pneumonia and multisystem inflammatory syndrome in children (MIS-C).

The two primary manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children are acute coronavirus disease 2019 (COVID-19) pneumonia and multisystem inflammatory syndrome (MIS-C). While most pediatric cases of acute COVID-19 disease are mild or asymptomatic, some children are at risk for developing severe pneumonia. In MIS-C, children present a few weeks after SARS-CoV-2 exposure with a febrile illness that can rapidly progress to shock and multiorgan dysfunction. In both diseases, the clinical and laboratory findings can be nonspecific and present a diagnostic challenge. Thoracic imaging is commonly obtained to assist with initial workup, assessment of disease progression, and guidance of therapy. This paper reviews the radiologic findings of acute COVID-19 pneumonia and MIS-C, highlights the key distinctions between the entities, and summarizes our understanding of the role of imaging in managing SARS-CoV-2-related illness in children.

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.

Imaging Findings in Multisystem Inflammatory Syndrome in Children (MIS-C) Associated With Coronavirus Disease (COVID-19).

BACKGROUND. A multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease (COVID-19) has recently been described. OBJECTIVE. The purpose of our study was to evaluate the imaging findings of MIS-C associated with COVID-19. METHODS. Imaging studies and medical records of patients (age range, 0-20 years) admitted with MIS-C between April 22 and May 21, 2020, were retrospectively reviewed. Thoracic imaging studies were evaluated for parenchymal, mediastinal and hilar, and cardiovascular abnormalities. Abdominal imaging studies were evaluated for abnormalities of solid viscera, hollow viscera, and the peritoneum as well as the mesentery and retroperitoneum. Studies were reviewed independently by two radiologists, and disagreements were resolved by a third senior radiologist. RESULTS. Sixteen patients (10 male and six female patients; age range, 20 months-20 years) were included in this study. All 16 patients presented with fever. Other presenting signs and symptoms included the following: vomiting (12/16, 75%), abdominal pain (11/16, 69%), rash (10/16, 63%), conjunctivitis (8/16, 50%), diarrhea (7/16, 44%), headache (6/16, 38%), and sore throat (5/16, 31%). Shortness of breath and cough were each present in one patient. Chest radiography showed cardiomegaly (10/16, 63%), congestive heart failure or cardiogenic pulmonary edema (9/16, 56%), atelectasis (9/16, 56%), pleural effusions (7/16, 44%), acute respiratory distress syndrome (2/16, 13%), and pneumonia (1/16, 6%). Eight patients (50%) were evaluated for pulmonary embolism (PE) (six [75%] by CT angiography [CTA] and two [25%] by ventilation-perfusion scintigraphy). In two of the eight patients (25%), CTA showed a segmental PE. Abdominal imaging findings (ultrasound, CT, and radiography) included small-volume ascites (6/16, 38%), hepatomegaly (6/16, 38%), echogenic kidneys (5/16, 31%), bowel wall thickening (3/16, 19%), gallbladder wall thickening (3/16, 19%), mesenteric lymphadenopathy (2/16, 13%), splenomegaly (1/16, 6%), and bladder wall thickening (1/16, 6%). The frequencies of findings based on all the reviewed modalities were as follows: cardiomegaly (12/16, 75%), pleural effusion (10/16, 63%), and atelectasis (10/16, 63%). Absolute interobserver agreement was 0.69-1 for thoracic findings and 0.17-1 for abdominal findings. Fifteen patients (94%) were discharged from the hospital (length of hospital stay: range, 3-20 days), and one patient remained in the hospital at the end of the study period. There were no mortalities. CONCLUSION. MIS-C associated with COVID-19 is characterized predominantly by cardiovascular abnormalities, although solid visceral organ, gallbladder, and bowel abnormalities as well as ascites are also seen, reflecting a multisystemic inflammatory process. CLINICAL IMPACT. The constellation of imaging findings in the setting of COVID-19 may alert radiologists to the diagnosis of MIS-C before rapid deterioration of patients.

Bladder prolapse through a patent urachus presenting as an umbilical mass in the newborn: characteristic prenatal sonographic findings and the diagnostic benefit of postnatal cystography.

Bladder prolapse through a patent urachus is rare. We present a newborn with an unusual exophytic, erythematous umbilical mass. Voiding cystography readily demonstrated continuity of the bladder dome with the umbilical mass, confirming bladder prolapse through a patent urachus. The diagnosis of bladder prolapse was rapidly made in a second newborn with similar imaging and clinical findings and confirmed by cystography. We discuss the embryology of this condition including the association with a vesico-allantoic cyst in utero. Pre- and postnatal images are presented. The use of cystography in diagnosis is emphasized.

Feasibility study of a novel portable digital radiography system modified for fluoroscopy in the neonatal intensive care unit.

BACKGROUND: A portable radiographic system capable of fluoroscopic imaging in the neonatal intensive care unit (NICU) potentially benefits critically ill neonates by eliminating the need to transport them to a fluoroscopy suite. OBJECTIVE: To evaluate whether a portable bedside fluoroscopy system in the NICU can deliver comparable image quality at a similar dose rate to a standard system in a fluoroscopy suite. MATERIALS AND METHODS: In phase A, 20 patients <3 years of age and scheduled to undergo upper gastrointestinal series (upper GI) or voiding cystourethrograms (VCUG) in the radiology fluoroscopy suite were recruited to evaluate a portable fluoroscopic unit. A modified portable radiographic system with a cassette-sized detector and an in-room fluoroscopy system were sequentially used in the same examination. Four radiologists compared the image quality of 20 images from each system using the Radlex score (1-4) for five image quality attributes. The radiation dose rates for the portable and in-suite systems were collected. In phase B, fluoroscopy studies were performed in 5 neonates in the NICU and compared to the 20 previous neonatal studies performed in the department. Clinical workflow, examination time, fluoroscopy time, scattered radiation dose and patient radiation dose were evaluated. RESULTS: In phase A, average dose rates for in-room and portable systems were equivalent, (0.322 mGy/min and 0.320 mGy/min, respectively). Reader-averaged Radlex scores for in-room and portable systems were statistically significantly greater (P<0.05) for all attributes on the portable system except for image contrast. In phase B, scattered radiation from the average fluoroscopy time (26 s) was equivalent to the scattered radiation of 2.6 portable neonatal chest radiographs. Procedure time and diagnostic quality were deemed equivalent. The average dose rate in the NICU with the portable system was 0.21 mGy/min compared to 0.29 mGy/min for the in-room system. CONCLUSION: The portable fluoroscopy unit is capable of providing comparable image quality at equivalent dose levels to an in-room system for neonates with minimal risks to the staff and other patients in the NICU.

Tailored Optimization of Pediatric Body MR Angiography for Successful Outcomes in Thoracic Applications.

OBJECTIVE. The purpose of this article is to describe optimized techniques for successful thoracic MR angiography (MRA) in children and to review examples of commonly encountered conditions. CONCLUSION. Successful MRA in children relies on considering the specific child and condition being evaluated and making appropriate choices about the most suitable modality, the use of anesthesia, and the best MRA techniques to determine a diagnosis.

CT, US and MRI of xanthine urinary stones: in-vitro and in-vivo analyses.

BACKGROUND: Xanthine urinary stones are a rare entity that may occur in patients with Lesch-Nyhan syndrome receiving allopurinol. There is little literature describing imaging characteristics of these stones, and the most appropriate approach to imaging these stones is therefore unclear. We performed in-vitro and in-vivo analyses of xanthine stones using computed tomography (CT) at different energy levels, ultrasound (US), and magnetic resonance imaging (MRI). METHODS: Five pure xanthine stones from a child with Lesch-Nyhan were imaged in-vitro and in-vivo. CT of the stones was performed at 80 kVp, 100 kVp, 120 kVp and 140 kVp and CT numbers of the stones were recorded in Hounsfield units (HU). US of the stones was performed and echogenicity, acoustic shadowing and twinkle artifact were assessed. MRI of the stones was performed and included T2-weighted, ultrashort echo-time-weighted and T2/T1-weighted 3D bFFE sequences and signal was assessed. RESULTS: In-vitro analysis on CT demonstrated that xanthine stones were radiodense and the average attenuation coefficient did not differ with varying kVp, measuring 331.0 ± 51.7 HU at 80 kVp, 321.4 ± 63.4 HU at 100 kVp, 329.7 ± 54.2 HU at 120 kVp and 328.4 ± 61.1 HU at 140 kVp. In-vivo analysis on CT resulted in an average attenuation of 354 ± 35 HU. On US, xanthine stones where echogenic with acoustic shadowing and twinkle artifact. On MRI, stones lacked signal on all tested sequences. CONCLUSION: Xanthine stone analyses, both in-vitro and in-vivo, demonstrate imaging characteristics typical of most urinary stones: dense on CT, echogenic on US, and lacking signal on MRI. Therefore, the approach to imaging xanthine stones should be comparable to that of other urinary stones.

Back to Fundamentals: Radiographic Evaluation of Thoracic Lines and Tubes in Children.

OBJECTIVE. The purpose of this article is to provide an up-to-date review of the radiographic appearance of the most commonly used thoracic lines and tubes in pediatric patients in daily clinical practice. CONCLUSION. Thoracic support lines and tubes are frequently used in children receiving hospital care. Evaluation of these devices is a fundamental skill in radiology. Many different devices are currently used, and new devices are regularly introduced. It is essential for radiologists to maintain a clear understanding of all devices currently in use.

Neonatal Lung Disorders: Pattern Recognition Approach to Diagnosis.

OBJECTIVE: Lung disease is a common indication for neonates to require medical attention, and neonatal chest radiographs are among the most common studies interpreted by pediatric radiologists. Radiographic features of many neonatal lung disorders overlap, and it may be difficult to differentiate among conditions. CONCLUSION: This review presents an up-to-date practical approach to the radiologic diagnosis of neonatal lung disorders, with a focus on pattern recognition and consideration of clinical history, patient age, and symptoms.

Updates on MRI Evaluation of Pediatric Large Airways.

OBJECTIVE: The purposes of this article are to present a practical approach to imaging of common congenital and acquired diseases of the pediatric large airways with MRI and to describe the imaging findings. CONCLUSION: High-quality MRI of the airways is an increasingly feasible alternative to conventional radiography, fluoroscopy, and CT in the evaluation of many diseases of the pediatric large airways.

Lung magnetic resonance imaging for pneumonia in children.

Technical factors have historically limited the role of MRI in the evaluation of pneumonia in children in routine clinical practice. As imaging technology has advanced, recent studies utilizing practical MR imaging protocols have shown MRI to be an accurate potential alternative to CT for the evaluation of pneumonia and its complications. This article provides up-to-date MR imaging techniques that can be implemented in most radiology departments to evaluate pneumonia in children. Imaging findings in pneumonia on MRI are also reviewed. In addition, the current literature describing the diagnostic performance of MRI for pneumonia is discussed. Furthermore, potential risks and limitations of MRI for the evaluation of pneumonia in children are described.

Three-dimensional ultrasound of the neonatal brain: technical approach and spectrum of disease.

Brain pathology is an important cause of morbidity and mortality in neonates, especially in the premature population. While conventional two-dimensional neurosonography is traditionally used for screening, diagnosis and monitoring of brain disorders such as germinal matrix hemorrhage, periventricular leukomalacia and hydrocephalus, three-dimensional ultrasonography has gained popularity in a variety of clinical applications in recent years. Three-dimensional ultrasonography is not yet widely utilized in pediatric imaging but is a potentially powerful tool for evaluating the neonatal brain. Three-dimensional neurosonography allows imaging of the entire brain in a single volumetric sweep and offers the capability of reconstructing images in the axial plane and performing volumetric analyses that are unavailable in conventional two-dimensional neurosonography. The purpose of this article is two-fold: (1) to present the technical aspects of three-dimensional neurosonography and (2) to illustrate the potential applications of three-dimensional neurosonography in the context of commonly encountered neonatal neuropathology.

Imaging of long gap esophageal atresia and the Foker process: expected findings and complications.

Long gap esophageal atresia (EA) is characterized by esophageal segments that are too far apart for primary anastomosis. Surgical repair utilizing interposition grafts or gastric transposition are often employed. The Foker staged lengthening procedure is an alternative surgical method that utilizes continuous traction on the esophagus to induce esophageal growth and allow for primary esophageal anastomosis. This pictorial review presents the step-by-step radiographic evaluation of the Foker procedure and illustrates the radiographic findings in the most commonly encountered complications in our cohort of 38 patients managed with this procedure from January 2000 to June 2012.

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.

Associating a standardized reporting tool for chest radiographs with clinical complications in pediatric acute chest syndrome.

BACKGROUND: Acute chest syndrome (ACS) is an important cause of morbidity in sickle cell disease (SCD). A standardized tool for reporting chest radiographs in pediatric SCD patients did not previously exist. OBJECTIVE: To analyze the interobserver agreement among pediatric radiologists' interpretations for pediatric ACS chest radiographs utilizing a standardized reporting tool. We also explored the association of radiographic findings with ACS complications. METHODS: This was a retrospective cohort study of pediatric ACS admissions from a single institution in 2019. ICD-10 codes identified 127 ACS admissions. Two radiologists independently interpreted the chest radiographs utilizing a standardized reporting tool, a third radiologist adjudicated discrepancies, and κ analysis assessed interobserver agreement. Clinical outcomes were correlated with chest radiograph findings utilizing Pearsons' χ2 , t tests, and Mann-Whitney U tests. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. RESULTS: Interobserver agreement was moderate to near-perfect across variables, with κ analysis showing near-perfect agreement for opacity reported in the right upper lobe (0.84), substantial agreement for right lower lobe (0.63), and vertebral bony changes (0.72), with moderate agreement for all other reported variables. On the initial chest radiograph, an opacity located in the left lower lobe (LLL) correlated with pediatric intensive care unit transfer (p = .03). Pleural effusion on the initial chest radiograph had a 3.98 OR (95% CI: 1.35-11.74) of requiring blood products and a 10.67 OR (95% CI: 3.62-31.39) for noninvasive ventilation. CONCLUSION: The standardized reporting tool showed moderate to near-perfect agreement between radiologists. LLL opacity, and pleural effusion were associated with increased risk of ACS complications.

Multidetector-row computed tomography enterographic assessment of the ileal-anal pouch: descriptive radiologic analysis with endoscopic and pathologic correlation.

OBJECTIVE: To describe the multidetector-row computed tomography enterographic (MD-CTE) features of the ileal-anal pouch after ileal pouch anal anastomosis (IPAA) surgery and correlate them with pouch endoscopy and histopathologic findings. METHODS: All MD-CTE examinations performed on patients who underwent IPAA from July 1, 2005 to December 1, 2010 (n = 35; 16 [45.7%] men; mean age, 37.7 years; age range, 22-72 years) were retrospectively evaluated in consensus by 2 radiologists. All studies were evaluated for the presence of multiple imaging features. Two radiographic scores were then calculated: a total radiographic score and a radiographic active inflammation score. In patients who underwent MD-CTE, pouch endoscopy, and biopsy within 30 days (n = 13), both scores were correlated with findings on pouch endoscopy and histopathology. RESULTS: Of the 35 patients, 33 (94%) had at least one MD-CTE finding of active or chronic pouch inflammation and 27 patients (77%) had at least one MD-CTE finding of active pouch inflammation. Of the 13 patients who underwent endoscopy and biopsy, the total radiographic score demonstrated a strong positive correlation with endoscopic score (r = 0.81; P = 0.001) and a moderate positive correlation with histopathologic score (r = 0.56; P = 0.047). The radiographic active inflammation score demonstrated a strong positive correlation with endoscopic score (r = 0.83; P = 0.0004), but only a weak nonsignificant positive correlation with histopathologic score (r = 0.492, P = 0.087). CONCLUSIONS: In patients who had IPAA surgery, findings on MD-CTE correlate positively with findings on pouch endoscopy and histopathology and are sensitive measures for pouch inflammation with high positive predictive value. Thus, MD-CTE can be a useful noninvasive test in the early evaluation of symptomatic patients.