Can Automated 3-Dimensional Dixon-Based Methods Be Used in Patients With Liver Iron Overload?

PURPOSE: Accurate quantification of liver iron concentration (LIC) can be achieved via magnetic resonance imaging (MRI). Maps of liver T2*/R2* are provided by commercially available, vendor-provided, 3-dimensional (3D) multiecho Dixon sequences and allow automated, inline postprocessing, which removes the need for manual curve fitting associated with conventional 2-dimensional (2D) gradient echo (GRE)-based postprocessing. The main goal of our study was to investigate the relationship among LIC estimates generated by 3D multiecho Dixon sequence to values generated by 2D GRE-based R2* relaxometry as the reference standard. METHODS: A retrospective review of patients who had undergone MRI scans for estimation of LIC with conventional T2* relaxometry and 3D multiecho Dixon sequences was performed. A 1.5 T scanner was used to acquire the magnetic resonance studies. Acquisition of standard multislice multiecho T2*-based sequences was performed, and R2* values with corresponding LIC were estimated. The comparison between R2* and corresponding LIC estimates obtained by the 2 methods was analyzed via the correlation coefficients and Bland-Altman difference plots. RESULTS: This study included 104 patients (51 male and 53 female patients) with 158 MRI scans. The mean age of the patients at the time of scan was 15.2 (SD, 8.8) years. There was a very strong correlation between the 2 LIC estimation methods for LIC values up to 3.2 mg/g (LIC quantitative multiecho Dixon [qDixon; from region of interest R2*] vs LIC GRE [in-house]: r = 0.83, P < 0.01; LIC qDixon [from segmentation volume R2*] vs LIC GRE [in-house]: r = 0.92, P < 0.01); and very weak correlation between the 2 methods at liver iron levels >7 mg/g. CONCLUSION: Three-dimensional-based multiecho Dixon technique can accurately measure LIC up to 7 mg/g and has the potential to replace 2D GRE-based relaxometry methods.

Imaging findings of children with PTEN-related hamartoma tumor syndrome: a 20-year multicentric pediatric cohort.

BACKGROUND: PTEN-related hamartoma tumor syndrome results from a mutation in the PTEN gene located at 10q23.31. This syndrome represents a spectrum of different phenotypes of variable expressions, now recognized as part of the same condition. Patients with this mutation have an increased risk of developing a wide range of findings, including malignancies. Although widely described in adults, there are no large series describing the imaging findings in patients before adulthood. Knowledge of the findings seen in children and adolescents with PTEN-related hamartoma tumor syndrome can help guide further management and improve surveillance recommendations. OBJECTIVE: To describe the spectrum of imaging abnormalities in pediatric patients with PTEN-related hamartoma tumor syndrome. MATERIALS AND METHODS: We performed a retrospective, cross-sectional, multicenter study conducted between January 2000 and October 2021 in three tertiary pediatric institutions evaluating the imaging findings in children and adolescents (≤ 18 years) with confirmed diagnoses of a PTEN mutation. For each patient, the imaging findings, histopathology reports, and at least a 2-year follow-up of clinical outcomes for non-operative cases were documented. RESULTS: The cohort included 78 children (37 girls), with a mean age at diagnosis of 7.5 years (range 0 days to 18 years). Benign brain findings included enlarged Virchow-Robin perivascular spaces, white matter changes, developmental venous anomalies, and cerebellar hamartomas. Benign thyroid findings were common, but 5/45 (11.1%) with thyroid abnormalities had a malignant nodule. Soft tissue adipocytic tumors, GI/GU polyps, other soft tissue abnormalities, along with vascular anomalies in various anatomic locations were common. CONCLUSION: Brain abnormalities, benign non-vascular soft tissue abnormalities, and vascular anomalies are commonly seen in children and adolescents with PTEN-related hamartoma tumor syndrome. However, malignancies involving the thyroid gland are not uncommon. Familiarity with the phenotype of PTEN-related hamartoma tumor syndrome in the pediatric population can improve diagnosis and prompt appropriate clinical surveillance of abnormal findings that warrant further management.

How we do it: Cardiac implantable devices are not a contraindication to MRI: time for a paradigm shift.

Magnetic resonance imaging (MRI) is now an indispensable diagnostic tool in medicine due to its outstanding contrast resolution and absence of radiation exposure, enabling detailed tissue characterization and three-dimensional anatomical representation. This is especially important when evaluating individuals with congenital heart disease (CHD) who frequently require cardiac implantable electrical devices (CIEDs). While MRI safety issues have previously limited its use in patients with CIEDs, new advances have called these limitations into question. However, difficulties persist in the pediatric population due to the continued lack of specific safety data both related to imaging young children and the specific CIED devices they often require. This paper discusses MRI safety considerations related to imaging patients with CIEDs, investigates pediatric-specific problems, and describes thorough methods for safe MRI access, highlighting the significance of specialized institutional guidelines.

Immunomodulatory drugs in sepsis: a systematic review and meta-analysis.

Dysregulation of the host immune response has a central role in the pathophysiology of sepsis. There has been much interest in immunomodulatory drugs as potential therapeutic adjuncts in sepsis. We conducted a systematic review and meta-analysis of randomised controlled trials evaluating the safety and clinical effectiveness of immunomodulatory drugs as adjuncts to standard care in the treatment of adults with sepsis. Our primary outcomes were serious adverse events and all-cause mortality. Fifty-six unique, eligible randomised controlled trials were identified, assessing a range of interventions including cytokine inhibitors; anti-inflammatories; immune cell stimulators; platelet pathway inhibitors; and complement inhibitors. At 1-month follow-up, the use of cytokine inhibitors was associated with a decreased risk of serious adverse events, based on 11 studies involving 7138 patients (RR (95%CI) 0.95 (0.90-1.00), I2 = 0%). The only immunomodulatory drugs associated with an increased risk of serious adverse events were toll-like receptor 4 antagonists (RR (95%CI) 1.18 (1.04-1.34), I2 = 0% (two trials, 567 patients)). Based on 18 randomised controlled trials, involving 11,075 patients, cytokine inhibitors reduced 1-month mortality (RR (95%CI) 0.88 (0.78-0.98), I2 = 57%). Mortality reduction was also shown in the subgroup of 13 randomised controlled trials that evaluated anti-tumour necrosis factor α interventions (RR (95%CI) 0.93 (0.87-0.99), I2 = 0%). Anti-inflammatory drugs had the largest apparent effect on mortality at 2 months at any dose (two trials, 228 patients, RR (95%CI) 0.64 (0.51-0.80), I2 = 0%) and at 3 months at any dose (three trials involving 277 patients, RR (95%CI) 0.67 (0.55-0.81), I2 = 0%). These data indicate that, except for toll-like receptor 4 antagonists, there is no evidence of safety concerns for the use of immunomodulatory drugs in sepsis, and they may show some short-term mortality benefit for selected drugs.

Quality and Diagnosis on the Lateral View of Pediatric Upper Gastro-Intestinal Series.

BACKGROUND: The standard imaging technique for the diagnosis of intestinal malrotation remains the upper gastro-intestinal series (UGIS). The lateral view is promoted as important for making a diagnosis. For this, the lateral view should be of adequate quality, and radiologists must know the normal appearance as well as the appearance of duodenal variants, as misdiagnosis may lead to unnecessary surgery. OBJECTIVE: We aimed to evaluate the quality, findings including the prevalence of the "descending staircase" configuration and its correspondence to a diagnosis of duodenum redundum. MATERIALS AND METHODS: This was a retrospective study and was conducted in a large tertiary children's hospital in the United States. A retrospective review of UGI fluoroscopy exams in children aged ≤ 18 years between January and December 2018 was performed by a pediatric radiologist. First, the lateral view images/cine-loops were assessed independently, followed by the anteroposterior (AP) view. The studies which were designated to have an adequate lateral view were evaluated for configuration of the duodenum and recorded as: normal, abnormal, or normal variant. Also, the presence of a descending staircase configuration was correlated with an AP view for a diagnosis of duodenum redundum. RESULTS: A total of 26 children (26%) (males:16; females:10) with age range 0 to 16 years had adequate lateral views during UGI exams for inclusion. Of the 26, 18 (69%) were reported as normal, 7 (27%) were reported as having a descending staircase and 1 (4%) was reported as abnormal. The AP view demonstrated 2 abnormal studies (1 malrotation and 1 non-rotation), 6 duodenum redundum and 18 normal exams. The one abnormal lateral duodenum was confirmed as a non-rotation on AP view; the second patient with an abnormal AP view had a normal appearance on the lateral view. CONCLUSIONS: A total of 26% of UGI studies had adequate lateral views for interpretation. Of these, nearly a quarter (23%) demonstrated the descending stair-case sign corresponding to a diagnosis of duodenum redundum on the AP view. If the lateral view had been used alone, there would have been a missed diagnosis in one patient.

A "global village": promoting research and careers in the pediatric radiology community through diversity.

There is a severe shortage of pediatric radiologists in the USA and across the globe due to multiple factors. These severe shortages, along with increased clinical demand, growing research costs and limited funding sources place pediatric radiologists, particularly those in academic departments, under increasing time pressure, affecting their ability to maintain research productivity. In this paper, we model a new concept that should help boost the research efforts within the pediatric radiology community, while diversifying the academic workforce through the involvement of international medical graduates (IMGs). We describe the mutual advantages this concept could have on academic pediatric radiology departments and IMGs alike, as well as pose some of the unique challenges that could impact this concept and effective strategies to ensure success.

Global pediatric radiology education: responding to training-level specific needs.

Pediatric radiology education for pediatric and radiology trainees and practicing professionals must be adapted to the target audience. In efforts to narrow the gaps in global pediatric radiology education, the Children's Hospital of Philadelphia's radiology department's Global Outreach and Education Program has designed specific interventions and curricula according to different levels of training and desired expertise. Our initiatives include an online "Introduction to Pediatric Imaging" lecture series for pediatrics residents in Botswana, Ethiopia and Vietnam; access to a learning management system (Outreach RADIAL) for radiology residents; case-based review sessions for pediatric radiology fellows; and in-person seminars for professionals from Eastern Europe and Africa. Here, we highlight our global education efforts to encourage other departments to take a similar systematic approach to outreach activities.

Case competition sessions: a global education and academic engagement tool.

BACKGROUND: Radiology virtual teaching sessions utilize live video conferencing to promote collaborative learning and engagement by discussing radiology cases. Because of its convenience and flexibility, this mode of education has gained popularity, particularly after the corona virus disease 2019 pandemic. OBJECTIVE: We describe our experience in organizing a series of "Global Health Imaging Case Competitions" for trainees in low- and middle-income countries (LMICs). These competitions provide the trainees with an opportunity to present unique radiology cases, network with radiologists, learn about various radiology topics, win prizes and potentially publish their case reports in a peer-reviewed journal. MATERIALS AND METHODS: Planning and execution of the competition involves several steps. First, trainees are invited to participate and submit abstracts discussing unique cases. The organizing committee grades these abstracts; the authors of the 20 abstracts with the highest scores are asked to submit a video presentation of their cases to be presented during the live webinar. During this webinar, presentations are displayed and graded to select winners. Additionally, the audience votes to choose a participant as the people's favorite. We have completed four cycles (Africa, Latin America and the Caribbean, Africa and the Middle East and Asia) and will continue in the same order of rotation. RESULTS: Attendance totalled 2,510 participants from 50 countries. Pediatric cases represented the majority of cases among finalists. Feedback was positive; 26 out of 29  (90%) participants surveyed indicated that the webinar was "very good" to "excellent" with well-organized and challenging cases. Diversity of participating countries was noted. Limitations included technology barriers such as internet connectivity. CONCLUSION: This innovative approach emphasizing audience participation engaged trainees from LMICs and fostered locoregional collegiality and mentoring.

Establishing pediatric radiology in a low-income country: the Ethiopian partnership experience.

In 2008, a partnership between the academic pediatric radiology department at the Children's Hospital of Philadelphia in the USA and the radiology department at Tikur Anbessa Specialized Hospital in Ethiopia, was established. The partnership aims to support pediatric radiology education during radiology residency and to establish pediatric radiology subspeciality training in Ethiopia. In this paper, we review the needs that elicit this type of partnership, its structure, achievements, challenges and future state as a successful roadmap to the establishment of a high-impact subspeciality program in a bilateral partnership.

Learning from experience - Radiology ancillary review of prospective research studies involving imaging.

This report describes the operational process of a big academic children's hospital's Radiology Scientific Review Committee, with a focus on its role in integrating radiology services into pediatric clinical research. We define the step-by-step workflow used to assess research proposals involving imaging and share insights from the past three years of data collection. Trends in modalities, radiologist involvement, and interpretation possibilities are outlined in the data. This systematic methodology provides essential resource allocation concepts and promotes high-quality pediatric clinical research.

Frequency of abnormal findings on chest radiograph after positive PPD in children and adolescents in an urban setting in the United States.

BACKGROUND: Chest radiographs (CXR) for tuberculosis (TB) screening in children are valuable in high-burden settings. However, less certain in low prevalence contexts. In the United States, positive PPD is sufficient to treat for "latent" TB, or TB infection in asymptomatic patients. OBJECTIVE: We sought to determine frequency of abnormal CXR findings after a positive purified protein derivative (PPD) test at a tertiary pediatric center in the United States. METHOD: A retrospective evaluation was conducted of patients (0-18 years) with a CXR after a positive PPD (e.g., known exposure, employment, migratory requirements or before immunosuppression) between 2011 and 2021. Clinical information, demographics, and reason for PPD were recorded from health record. CXRs were evaluated using initial report and by a pediatric radiologist with special interest in TB and 8 years of experience. RESULT: Of 485 patients, median [interquartile range (IQR)] age 8.5[3.3-14.4], abnormal CXRs were described in 5 (1%). Most common reasons for PPD included: close contact with someone with TB or with high risk for TB. Most patients 373 (76.9%) received treatment for latent TB, and 111 (22.9%) no treatment. One patient (0.2%) received treatment for active disease. Radiographic findings included isolated lymphadenopathy (n = 2), consolidation (n = 1), pleural fluid/thickening (n = 1) and a patient with lymphadenopathy and a calcified nodule (n = 1). CONCLUSION: In our experience, prevalence of chest radiographs findings for patients with positive PPD was very low. Moreover, no cases of severe disease were seen and those with abnormal findings would not merit treatment change under current WHO guidelines.

Imaging of Vesicoureteral Reflux: AJR Expert Panel Narrative Review.

Vesicoureteral reflux (VUR) is a common congenital anomaly of the urinary tract that can present with collecting system dilation or as a febrile infection. VUR can lead to permanent renal sequela requiring surgery but can also spontaneously resolve without complication. Therefore, it is important to recognize those patient populations who warrant imaging for screening, confirmation, or ongoing surveillance for VUR, while avoiding overdiagnosis. In the appropriate patient populations, an accurate diagnosis of VUR allows early treatment and prevention of pyelonephritis and scarring. Various imaging modalities are available to diagnose and grade VUR, including voiding cystourethrogram (VCUG), radionucleotide cystography (RNC), and contrast-enhanced voiding urosonography (ceVUS). The objective of this article is to summarize the current understanding of VUR diagnosis and management and to discuss these imaging modalities' strengths and pitfalls. Considerations include indications for VUR imaging, patient preparation, conduct of the examination, issues related to radiologic reporting, and cost-effectiveness. An emphasis is placed on ceVUS, which is the most recently introduced of the three imaging modalities and is receiving growing support among pediatric radiologists.

MRI scarcity in low- and middle-income countries.

Since the introduction of MRI as a sustainable diagnostic modality, global accessibility to its services has revealed a wide discrepancy between populations-leaving most of the population in LMICs without access to this important imaging modality. Several factors lead to the scarcity of MRI in LMICs; for example, inadequate infrastructure and the absence of a dedicated workforce are key factors in the scarcity observed. RAD-AID has contributed to the advancement of radiology globally by collaborating with our partners to make radiology more accessible for medically underserved communities. However, progress is slow and further investment is needed to ensure improved global access to MRI.