Gated cardiac CT in infants: What can we expect from deep learning image reconstruction algorithm?

BACKGROUND: ECG-gated cardiac CT is now widely used in infants with congenital heart disease (CHD). Deep Learning Image Reconstruction (DLIR) could improve image quality while minimizing the radiation dose. OBJECTIVES: To define the potential dose reduction using DLIR with an anthropomorphic phantom. METHOD: An anthropomorphic pediatric phantom was scanned with an ECG-gated cardiac CT at four dose levels. Images were reconstructed with an iterative and a deep-learning reconstruction algorithm (ASIR-V and DLIR). Detectability of high-contrast vessels were computed using a mathematical observer. Discrimination between two vessels was assessed by measuring the CT spatial resolution. The potential dose reduction while keeping a similar level of image quality was assessed. RESULTS: DLIR-H enhances detectability by 2.4% and discrimination performances by 20.9% in comparison with ASIR-V 50. To maintain a similar level of detection, the dose could be reduced by 64% using high-strength DLIR in comparison with ASIR-V50. CONCLUSION: DLIR offers the potential for a substantial dose reduction while preserving image quality compared to ASIR-V.

Prenatal magnetic resonance imaging of complex female genitourinary system abnormalities, what the fetal medicine specialist needs to know.

Complex female genitourinary system anomalies include a wide spectrum of uncommon pathologies, caused from the abnormal separation of the urorectal septum and the urogenital sinus in early embryonic life. The resulting fusion of the distal urinary, genital and intestinal tracts increases the risk of death in utero and alters the normal organ functionality and the quality of life in survivors. An accurate prenatal identification of these pathologies depends mainly on prior suspicion at ultrasound screening, but also requires a solid knowledge of embryology and familiarity with the different patterns of malformation. Prenatal MRI provides an excellent anatomic evaluation of the fetal anatomy that may improve the diagnosis in complex cases with inconclusive echographic findings. The additional information can help both families and medical teams to better evaluate the severity of the pathology and the postnatal prognosis and therefore to better orientate the management during pregnancy, at delivery and after birth. This review article describes the embryological basis and the clinical findings of the most relevant pathologies included in the spectrum. It also describes the imaging signs on prenatal MRI studies in a series of confirmed cases and proposes a diagnostic algorithm based on imaging findings for guiding prenatal diagnosis.

Necrotizing pneumonia in children: Chest computed tomography vs. lung ultrasound.

Background: The utilization of contrast-enhanced computed tomography (CT) of the chest for the diagnosis of necrotizing pneumonia (NP), a complication of community-acquired pneumonia, is controversial because of the inherent ionizing radiation involved. Over the past few years, the growing availability of bedside Lung Ultrasound (LUS) devices has led to increased use of this nonionizing imaging method for diagnosing thoracic pathology, including pneumonia. Objective: The objectives of this study were as follows: first, to compare the performance of LUS vs. CT in the identification of certain radiological signs of NP, and second, to determine whether LUS could replace CT in the diagnosis of NP. Materials and methods: We compared retrospectively the CT and LUS images of 41 patients between 2005 and 2018 in whom at least one contrast-injected chest CT scan and one LUS had been undertaken fewer than 7 days apart. Results: Pleural effusions were demonstrated almost systematically (100% on CT vs. 95.8% on LUS). Visualization of septations in pleural effusions was clearly superior on LUS (20.4% on CT vs 62.5% on LUS). Concerning the detection of necrosis, we observed a strong correlation between LUS and the gold-standard CT (95.8% on LUS vs. 93.7% on CT). Parenchymal cavities were more easily detected on CT than on LUS (79.1 vs. 35.4%). Conclusion: LUS has shown to be as effective as CT in the diagnosis of NP. The use of CT in patients with NP could be limited to the detection of complications such as bronchopleural fistulae in unfavorably evolving diseases.

Contribution of magnetic resonance imaging to the prenatal diagnosis of common congenital vascular anomalies.

BACKGROUND: Screening ultrasound (US) has increased the detection of congenital vascular anomalies in utero. Complementary magnetic resonance imaging (MRI) may improve the diagnosis, but its real utility is still not well established. OBJECTIVES: We aimed to describe the imaging findings on prenatal US and MRI of the most frequent congenital vascular anomalies (lymphatic malformations and congenital hemangiomas) to assess the accuracy of prenatal US and MRI exams for diagnosis and to evaluate the relevance of the additional information obtained by complementary fetal MRI. MATERIALS AND METHODS: All confirmed postnatal congenital vascular anomalies detected in the last 10 years at 3 university hospitals were retrospectively identified. The prenatal diagnosis was compared with the final diagnosis for both methods and the clinical relevance of additional MRI information was evaluated. A second MRI in advanced pregnancy was performed in fetuses with lesions in a sensitive anatomical location and the clinical relevance of the additional information was evaluated. RESULTS: Twenty-four cases were included in the study, 20 lymphatic malformations and 4 hemangiomas. MRI slightly improved the diagnosis of lymphatic malformation, 85% vs. 80% at US, especially for abdominal lesions. Both methods had a low identification rate (25%) for tumors. MRI performed late in five fetuses with lymphatic malformation allowed optimized management at birth. CONCLUSION: MRI improves the diagnosis of congenital lymphatic malformations whereas hemangiomas remain difficult to identify in utero. The main role of MRI is to provide high-defined anatomical data to guide management at birth.

Revising the classification of lung sequestrations.

PURPOSES: The classification of lung sequestrations distinguishes between extralobar and intralobar types, according to their venous drainage - systemic vs pulmonary - and the presence or absence of independent pleura. However, imaging, surgical and/or pathological findings often differ from this description. The objectives of this article are to quantify the percentage of lung sequestrations that do not fit the classic description of extra- and intralobar types and to evaluate the accuracy of the currently used classification. METHODS: A retrospective search identified all children with a confirmed lung sequestration diagnosed and treated in our Hospital over the last 10 years. Two senior pediatric radiologists reviewed their contrast-enhanced computed tomography chest scans and evaluated the main anatomical features that define sequestrations, including pleura, arterial and venous pattern, airways and lung parenchyma. We compared the imaging-, surgical- and pathological findings to those described for extra- and intralobar sequestrations. RESULTS: 25 children (20 M, 5 F) conform the series. Only 13 lesions (52%) filled all criteria described for an extra- or intralobar sequestration. The remaining 12 lesions (48%) had at least one differing criteria, including incomplete independent pleura (n = 2; 8%), mixed systemic and pulmonary arterial supply (n = 1; 4%) or venous drainage (n = 3; 12%), normal connection to airway (n = 1; 4%) and/or coexistent congenital lung anomalies (n = 11; 44%). CONCLUSION: Lung sequestrations seem to represent a spectrum of anomalies rather than separated entities. Therefore, a detailed description of their main anatomical features could be more relevant for clinicians and surgeons that the rigid distinction in intra- and extralobar sequestration currently applied.

Prenatal imaging of anorectal malformations - 10-year experience at a tertiary center in Switzerland.

BACKGROUND: Anorectal malformation is a spectrum of congenital defects of the distal bowel, mostly diagnosed at birth. OBJECTIVE: To describe the prenatal imaging findings of anorectal malformations, explore the causes of the low rates of prenatal diagnosis, compare the accuracy of prenatal ultrasound (US) and magnetic resonnance imaging [MRI] and evaluate the relevance of information obtained at MRI. MATERIALS AND METHODS: Children treated for anorectal malformation at our hospital and with available prenatal studies were retrospectively identified and included in the study. We reviewed prenatal imaging exams, listed findings suggestive of the diagnosis, and compared results with the final classification. RESULTS: Fourteen fetuses and neonates - eight with intermediate-high type anorectal malformation and six with cloacae - fulfilled the inclusion criteria. All had associated congenital anomalies. Prenatal exams included 13 US and 8 MRI exams, with 7 children having both exams. Suggestive findings for anorectal malformation were detected in 50% of the cases prenatally and in 85% upon review. They were prospectively detected in 31% and 50% of the cases at US and MRI and retrospectively in 62% and 100% at US and MRI, respectively. MRI was superior to US because it improved the diagnosis, especially in cloacae, and provided relevant additional information that changed management in two cases. CONCLUSION: The most important signs suggesting anorectal malformation are an absent target sign and anomalous distal bowel wall and rectal fluid. Complementary prenatal MRI improves the diagnosis of anorectal malformation.

Author Correction: Fetal cardiac cine magnetic resonance imaging in utero.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

MRI findings of complications related to previous uterine scars.

Although the World Health Organization suggests 10-15% as the adequate cesarean delivery rate to assure optimal prognosis for mother and children, cesarean rates have continuously increased worldwide over the last three decades, even in primiparous women. Moreover, uterine scars after myomectomies, complications of obstetrical interventions and more recently, after fetal surgery, are often observed. This review article describes the most commonly seen complications related to prior uterine scars and discusses their imaging findings, with emphasis on the increasing role of Magnetic Resonance Imaging for diagnosis.

Pre- and neonatal imaging of gastrointestinal complications in congenital diaphragmatic hernia.

The initial outcome in infants with congenital diaphragmatic hernia is mainly related to the associated lung hypoplasia. However, these patients frequently present with additional gastrointestinal pathology that also influences their quality of life and final prognosis. Congenital gastrointestinal anomalies are often observed and the displacement of the liver, the stomach and/or the intestines into the thorax may cause distortion of the vascular axis of these organs, increasing the risk of congestion and/or ischemia. Some of these gastrointestinal complications are already visible at imaging studies performed in utero and/or in newborns.This pictorial essay describes the imaging findings of the most frequently detected gastrointestinal complications in fetuses and infants with congenital diaphragmatic hernia, focusing on prenatal exams.

Fetal cardiac cine magnetic resonance imaging in utero.

Fast magnetic resonance imaging (MRI) led to the emergence of 'cine MRI' techniques, which enable the visualization of the beating heart and the assessment of cardiac morphology and dynamics. However, established cine MRI methods are not suitable for fetal heart imaging in utero, where anatomical structures are considerably smaller and recording an electrocardiogram signal for synchronizing MRI data acquisition is difficult. Here we present a framework to overcome these challenges. We use methods for image acquisition and reconstruction that robustly produce images with sufficient spatial and temporal resolution to detect the heart contractions of the fetus, enabling a retrospective gating of the images and thus the generation of images of the beating heart. To underline the potential of our approach, we acquired in utero images in six pregnant patients and compared these with their echocardiograms. We found good agreement in terms of diameter and area measurements, and low inter- and intra- observer variability. These results establish MRI as a reliable modality for fetal cardiac imaging, with a substantial potential for prenatal evaluation of congenital heart defects.

Prenatal imaging of congenital hepatic tumors: a report of three cases.

The generalization of screening pregnancy ultrasound (US) studies has increased the detection of congenital tumors, including hepatic masses. In these cases, prenatal MRI is often used as a complementary imaging study. We present three cases of congenital hepatic tumors-two hemangiomas and one hamartoma-detected in utero and followed up in our institution. The retrospective analysis of their US and MRI prenatal imaging findings shows significant overlapping, indicating that the characterization of congenital hepatic tumors based exclusively on imaging findings is challenging.

Magnetic resonance imaging of fetal pelvic cysts.

The detection of fetal anomalies has improved in the last years as a result of the generalization of ultrasound pregnancy screening exams. The presence of a cystic imaging in the fetal pelvis is a relatively common finding, which can correspond to a real congenital cystic lesion or result from the anomalous liquid accumulation in a whole pelvic organ, mainly the urinary bladder, the uterus, or the vagina. In selected cases with poor prognosis and/or inconclusive echographic findings, magnetic resonance may bring additional information in terms of the characterization, anatomical location, and real extension of the pathology. This pictorial essay describes the normal pelvic fetal anatomy, as well as the most common pelvic cysts. It also describes the causes of an anomalous distension of the whole pelvic organs detected in utero, with emphasis on prenatal magnetic resonance imaging exams. Moreover, it proposes practical teaching points to reduce the differential diagnosis of these lesions based on the sex of the fetus, the division of the pelvis in anatomical spaces, and the imaging findings of the pathology. Finally, it discusses the real utility of complementary MRI.

Performance of post-mortem CT compared to autopsy in children.

INTRODUCTION: Radiological techniques such as non-enhanced post-mortem computed tomography (PMCT) play an increasingly important role in death investigations, especially in cases of non-medicolegal context of death, where the consent of the next of kin is required to perform autopsy. Such consent is often difficult to obtain for deceased children, and radiological methods may be an acceptable alternative. The aim of our study was to evaluate the performance of PMCT explorations compared to medicolegal conventional autopsies in children and its potential usefulness in non-medicolegal situations. METHODS: We retrospectively reviewed a group of 26 children aged 0-12 years who died of different causes, which were investigated by both conventional autopsy and PMCT. We compared the findings extracted from radiological and autopsy reports. All findings were grouped according to their importance with respect to cause of death and to the anatomical structure they covered: organs, vascular system, soft tissue, and skeletal system. RESULTS: A significantly larger number of findings were detected by autopsy compared to PMCT. Autopsy proved to be superior to PMCT, notably at detecting organ, soft tissue, and vascular findings, while PMCT was superior at detecting bone findings. However, no statistically significant differences were found between the methods concerning the essential findings used to define the cause of death. CONCLUSIONS: In children, PMCT was less sensitive than conventional autopsy for detecting general findings. However, most essential findings were detected by both methods. PMCT was superior to autopsy for the detection of bone lesions in children. ADVANCES IN KNOWLEDGE: Up to today, very rare literature exists concerning PMCT in children, especially in a forensic setting. This article investigates the advantages and limitations of PMCT compared to autopsy in a unique study group and discusses possibilities for future developments.

Imaging findings of bronchial atresia in fetuses, neonates and infants.

Congenital lung malformations are increasingly detected before birth. However, bronchial atresia is rarely identified in utero and not always recognized in neonates. There are two types of atresia: 1) proximal, located at the level of the mainstem or the proximal lobar bronchi, which is extremely rare and usually lethal during pregnancy, causing a tremendous volume increase of the distal involved lung with secondary hypoplasia of the normal lung, and 2) peripheral, located at the segmental/subsegmental bronchial level, which may present as an isolated lesion or as part of a complex congenital malformation. Prenatal findings are mostly nonspecific. Postnatal exams show overinflated lung areas and focal bronchial dilations. The typical fluid-filled bronchoceles are not always observed in neonates but develop progressively in the first months of life. This pictorial essay describes the spectrum of imaging findings of bronchial atresia in fetuses, neonates and infants.

[Patients with variations of sex development : an example of interdisciplinary care]. / Patients avec variation du développement sexuel : un exemple de prise en charge interdisciplinaire.

The medical, psychological and social aspects of disorders of sex development (DSD) represent a challenge for the management of these patients. However, advances in our understanding of the etiology and genetics of this condition, novel surgical approaches and the growing influence of patient groups as well as wider recognition of ethical issues have helped improve the care of patients with a DSD. Importantly, a multidisciplinary approach involving specialists is crucial for understanding and treating such rare and complex cases. According to the recommendations of the Swiss National Ethical Commission, we shall use the term « Variation of Sex Development ¼ rather than « Disorder of Sex Development ¼ in this publication. This article addresses the care of DSD patients throughout development from the point of view of specialists in complementary fields.

La prise en charge des personnes avec une variation du développement sexuel (VDS) (disorder of sex development, DSD) est un défi tant sur le plan médical, psychologique que social. L'amélioration des connaissances étiologiques et génétiques, les nouvelles approches chirurgicales et l'influence tant des groupes de patients que de la Commission d'éthique suisse ont considérablement modifié la vision de la prise en charge de ces personnes durant ces dernières décennies. Une approche pluridisciplinaire et spécialisée est cruciale pour appréhender ces situations rares et souvent complexes. Le point de vue des différents spécialistes impliqués au long de la vie dans la prise en charge d'une VDS est abordé dans cet article.

Surgical complications due to postnatal cytomegalovirus infection in a preterm infant with malrotation.

We report a case of an extremely preterm infant with intestinal malrotation who contracted postnatal systemic cytomegalovirus (CMV) infection with a complicated intestinal evolution requiring repeated surgical interventions and antiviral treatment. This report is to emphasize that prolonged gastrointestinal symptoms in extremely preterm infants fed with non-pasteurized breast milk should lead to suspicion of CMV infection. The importance of preventive measures when feeding very preterm infants with breast milk needs to be considered. Furthermore, the indications for antiviral treatment, in particular in preterm infants, need to be clarified.

Biomarkers of Host Response Predict Primary End-Point Radiological Pneumonia in Tanzanian Children with Clinical Pneumonia: A Prospective Cohort Study.

BACKGROUND: Diagnosing pediatric pneumonia is challenging in low-resource settings. The World Health Organization (WHO) has defined primary end-point radiological pneumonia for use in epidemiological and vaccine studies. However, radiography requires expertise and is often inaccessible. We hypothesized that plasma biomarkers of inflammation and endothelial activation may be useful surrogates for end-point pneumonia, and may provide insight into its biological significance. METHODS: We studied children with WHO-defined clinical pneumonia (n = 155) within a prospective cohort of 1,005 consecutive febrile children presenting to Tanzanian outpatient clinics. Based on x-ray findings, participants were categorized as primary end-point pneumonia (n = 30), other infiltrates (n = 31), or normal chest x-ray (n = 94). Plasma levels of 7 host response biomarkers at presentation were measured by ELISA. Associations between biomarker levels and radiological findings were assessed by Kruskal-Wallis test and multivariable logistic regression. Biomarker ability to predict radiological findings was evaluated using receiver operating characteristic curve analysis and Classification and Regression Tree analysis. RESULTS: Compared to children with normal x-ray, children with end-point pneumonia had significantly higher C-reactive protein, procalcitonin and Chitinase 3-like-1, while those with other infiltrates had elevated procalcitonin and von Willebrand Factor and decreased soluble Tie-2 and endoglin. Clinical variables were not predictive of radiological findings. Classification and Regression Tree analysis generated multi-marker models with improved performance over single markers for discriminating between groups. A model based on C-reactive protein and Chitinase 3-like-1 discriminated between end-point pneumonia and non-end-point pneumonia with 93.3% sensitivity (95% confidence interval 76.5-98.8), 80.8% specificity (72.6-87.1), positive likelihood ratio 4.9 (3.4-7.1), negative likelihood ratio 0.083 (0.022-0.32), and misclassification rate 0.20 (standard error 0.038). CONCLUSIONS: In Tanzanian children with WHO-defined clinical pneumonia, combinations of host biomarkers distinguished between end-point pneumonia, other infiltrates, and normal chest x-ray, whereas clinical variables did not. These findings generate pathophysiological hypotheses and may have potential research and clinical utility.

Multiphase Postmortem Computed Tomography Angiography in Pediatrics: A Case Report.

Postmortem imaging techniques, especially postmortem computed tomography, have become integral tools in forensic investigations. Multiphase postmortem computed tomography angiography (MPMCTA) visualizes the vascular system in detail and makes it possible to evaluate the perfusion of even the smallest vessels. Although the technique has been well described for adults, no pediatric cases have been reported and no pediatric protocol has been established for this type of investigation. We present the case a 7-year-old child for which we used a previously described MPMCTA protocol and adapted values of perfusion, with the same technical equipment as for adult cases. Our main objective was to propose a perfusion protocol adapted for the investigation of infants and children. Moreover, we discuss both the difficulties that we encountered and possible ways to further improve the investigation of pediatric cases by MPMCTA.

Imaging findings in fetal diaphragmatic abnormalities.

Imaging plays a key role in the detection of a diaphragmatic pathology in utero. US is the screening method, but MRI is increasingly performed. Congenital diaphragmatic hernia is by far the most often diagnosed diaphragmatic pathology, but unilateral or bilateral eventration or paralysis can also be identified. Extralobar pulmonary sequestration can be located in the diaphragm and, exceptionally, diaphragmatic tumors or secondary infiltration of the diaphragm from tumors originating from an adjacent organ have been observed in utero. Congenital abnormalities of the diaphragm impair normal lung development. Prenatal imaging provides a detailed anatomical evaluation of the fetus and allows volumetric lung measurements. The comparison of these data with those from normal fetuses at the same gestational age provides information about the severity of pulmonary hypoplasia and improves predictions about the fetus's outcome. This information can help doctors and families to make decisions about management during pregnancy and after birth. We describe a wide spectrum of congenital pathologies of the diaphragm and analyze their embryological basis. Moreover, we describe their prenatal imaging findings with emphasis on MR studies, discuss their differential diagnosis and evaluate the limits of imaging methods in predicting postnatal outcome.

MR and CT imaging of pulmonary valved conduits in children and adolescents: normal appearance and complications.

BACKGROUND: The Contegra® is a conduit made from the bovine jugular vein and then interposed between the right ventricle and the pulmonary artery. It is used for cardiac malformations in the reconstruction of right ventricular outflow tract. OBJECTIVE: To describe both normal and pathological appearances of the Contegra® in radiological imaging, to describe imaging of complications and to define the role of CT and MRI in postoperative follow-up. MATERIALS AND METHODS: Forty-three examinations of 24 patients (17 boys and 7 girls; mean age: 10.8 years old) with Contegra® conduits were reviewed. Anatomical description and measurements of the conduits were performed. Pathological items examined included stenosis, dilatation, plicature or twist, thrombus or vegetations, calcifications and valvular regurgitation. Findings were correlated to the echographic gradient through the conduit when available. RESULTS: CT and MR work-up showed Contegra® stenosis (n = 12), dilatation (n = 9) and plicature or twist (n = 7). CT displayed thrombus or vegetations in the Contegra® in three clinically infected patients. Calcifications of the conduit were present at CT in 12 patients and valvular regurgitation in three patients. The comparison between CT and/or MR results showed a good correlation between the echographic gradient and the presence of stenosis in the Contegra®. CONCLUSION: CT and MR bring additional information about permeability and postoperative anatomy especially when echocardiography is inconclusive. Both techniques depict the normal appearance of the conduit, and allow comparison and precise evaluation of changes in the postoperative follow-up.