Safety of gadoterate meglumine in children younger than 2 years of age.

BACKGROUND: Few studies on the safety of gadolinium-based contrast agents have been performed in children with even fewer focusing on children younger than 2 years of age. OBJECTIVE: To assess the safety of gadoterate meglumine (Dotarem) in patients younger than 2 years of age by evaluating adverse events following contrast administration. MATERIALS AND METHODS: Pediatric patients younger than 2 years of age undergoing magnetic resonance imaging (MRI) with and without contrast were prospectively enrolled and received a weight-based intravenous dose of gadoterate meglumine (0.1 mmol/kg). The occurrence of adverse events was assessed at the time of injection, 2 h after MRI, and by phone contact using a standard questionnaire 24 h after MRI. Adverse events were documented including the time of onset, duration of symptoms, intensity, causality and subsequent outcome. Descriptive statistics were used to characterize patient information. RESULTS: One hundred fifty exams were completed in 150 patients (median age: 12.1 months, age range: 0.25-23 months; males: 56%). Almost all patients (97.3%) received sedation/anesthesia before and during MRI. Thirty-four adverse events were reported in 23 patients overall (15.3%; male: 73.9%; median age: 11 months, age range: 3-23 months). Within the initial 2 h after the injection, there was one report of transient flushing/warmth and one report of vomiting, the latter of which was related to drinking formula too soon after anesthesia. Twenty-two patients (14.7%), who had all received sedation/anesthesia, experienced minor adverse events within 24 h, most physiological. Fourteen patients (9.3%) reported emesis, eight (5.3%) reported transient flushing/warmth, seven (4.7%) reported nausea, one (0.7%) reported altered taste and one (0.7%) reported dizziness. No patient experienced anaphylaxis. Two patients (1.3%) reported allergic-like reactions, which consisted of wheezing or sneezing. CONCLUSION: No patient experienced adverse events directly related to gadoterate meglumine. Only two adverse events were reported to have occurred in the initial 2 h after the exam, while the rest were reported on the 24-h follow-up call. The higher reported rate of adverse events in this study may be related to concomitant sedation/anesthesia as well as to overreporting from parents on the 24-h follow-up questionnaire. The study confirms a good safety profile for gadoterate meglumine in this very sensitive population.

Solid tumor screening recommendations in trisomy 18.

The purpose of this study was to determine whether trisomy 18 patients are at an increased risk of tumor development and require formal tumor screening recommendations. A literature search of trisomy 18 patients with reports of tumors or malignancies, and compilation of all previously reported as well as new unreported cases was performed. 67 patients with trisomy 18 were found to have documented malignancies. 44 patients had hepatoblastomas, 21 patients had Wilms tumors, one patient had a functional neurogenic neoplasia, and one patient had Hodgkins lymphoma. The increasing numbers of reported malignancies in patients with trisomy 18 supports the indication for an early screening process. Specific screening recommendations are outlined consisting of imaging exams and laboratory values performed at specific intervals.

Pancreatic heterotopia in a neonatal abdominopelvic cyst.

Pancreatic heterotopia is a rare congenital anomaly more commonly incidentally found in adults. While intra-abdominal cysts found on prenatal imaging are not uncommon, we examine a case of pancreatic heterotopia presenting in an abdominopelvic cyst on prenatal imaging. At birth, the neonate was found to have hypoglycemia unresponsive to treatment that resolved after cyst resection. We will review the etiology, imaging findings and clinical course of this anomaly, which should be considered in the differential diagnosis of newborns presenting with unexplained hypoglycemia.

Association between ventricular shunt catheter calcifications and the development of shunt fracture.

BACKGROUND: Calcifications along ventricular catheters have been associated with shunt fractures although it is unknown whether their development predicts whether and when the shunts will fracture. OBJECTIVE: To determine whether extracranial calcifications found on a radiographic shunt series predicts whether a patient will experience a shunt catheter fracture or complication. MATERIALS AND METHODS: A retrospective review was performed of pediatric patients with a ventricular shunt placed before 18 years of age and radiographic shunt series. Two thousand, six hundred and thirty shunt series in 523 patients (301 male) were reviewed to identify the development of calcifications around the catheter and fracture. Fifty-one patients were excluded for preexisting calcifications with shunt fracture. (48) Absence of shunt (2) or age (1). Analysis included descriptive statistics, odds ratio and chi-square test results. RESULTS: Four hundred seventy-two patients were included. Of the 59 shunts in 58 patients that developed calcifications, 23 went on to fracture (39%). Forty shunts without calcification in 37 patients developed fractures. There is a significant positive association between calcification and fracture (Χ2=39.1, P<0.01). It is 6.12 times more likely that a fractured shunt had calcifications compared to a non-fractured shunt having calcifications. Calcifications appeared within an average of 9 years, 10 months (range: 4-14 years) after shunt insertion. Shunt fractures occurred within an average of 5 years, 2 months (range: 6 months-9 years) after the appearance of calcifications with a median patient age of 14.6 years. Nearly all fractures were at or adjacent to the calcifications, most commonly in the neck (17/23; 73.9%). CONCLUSION: Shunt calcification represents a significant risk for catheter fracture in the pediatric population. Early intervention or closer interval follow-up may be indicated in those found to have calcifications.

Shear wave elastography correlates with liver fibrosis scores in pediatric patients with liver disease.

BACKGROUND: While liver biopsy remains the gold standard, given the procedure risks and sampling errors, there is a need for reliable noninvasive biomarkers of hepatic fibrosis. OBJECTIVE: Determine the accuracy of two-dimensional shear wave elastography (2-D SWE) in predicting the histological severity of liver fibrosis in pediatric patients with known or suspected liver disease. MATERIALS AND METHODS: Subjects 0-18 years old with known or suspected liver disease and liver biopsy within 30 days (n=70) were included. Comparisons by 2-D SWE were made to a control group (n=79). Two-dimensional SWE was performed using the GE LOGIQ E9 system. Liver biopsy specimens were scored according to METAVIR and Ishak scoring systems using Spearman's Rho correlation. Receiver operator characteristic (ROC) analysis, Kruskal-Wallis and Mann-Whitney U tests were conducted. RESULTS: Control group median 2-D SWE measurements were lower than in subjects with any degree of liver fibrosis (P<0.001). Those with METAVIR F0 and Ishak 0 scores had significantly lower median 2-D SWE measurements (1.35 m/s; 1.36 m/s) than those with more advanced liver disease (F1-F3: 1.49-1.62 m/s; 1-4: 1.45-1.63 m/s) (P<0.05 for all), whereas the 2-D SWE in the higher scores were similar. Results did not differ between METAVIR and Ishak scores for any degree of fibrosis. Fibrosis scores moderately correlated with median 2-D SWE measurements (rs=0.43). The area under the curve for F1 compared to combined control/F0 was 0.89 (95% confidence interval [CI] 0.83-0.95; P<0.001) with sensitivity of 94.6% and specificity of 78.6%. Results for Ishak score 1 were similar. The ideal cutoff value for identifying fibrosis was determined to be 1.29 m/s. CONCLUSION: The liver 2-D SWE measurements correlated with the histological liver fibrosis scores, regardless of the histopathological scoring system, although 2-D SWE was better at identifying patients with early fibrosis, not at distinguishing among the individual fibrosis levels. Two-dimensional SWE using the GE LOGIQ US system is useful for identifying pediatric patients at risk for liver fibrosis.

Changes in factors influencing fellowship choices among radiology residents from 2008 to 2018 and methods that may increase interest in the pediatric radiology subspecialty.

BACKGROUND: Fewer residents are choosing a career in pediatric radiology, which is contributing to an ongoing shortage of pediatric radiologists. OBJECTIVE: To identify potential causes of reduced interest in pediatric radiology as a career given a projected worsening of a nationwide shortage of pediatric radiologists. MATERIALS AND METHODS: An online questionnaire using previously published questions was approved and distributed by the Program Directors in Diagnostic Radiology to diagnostic radiology residents on behalf of the Society for Pediatric Radiology (SPR). Descriptive statistics including means with standard error and independent t-tests were used to compare mean scores between survey years. RESULTS: Nearly all of the 353 respondents (90.9%) planned on pursuing a fellowship. The majority (57.7%) identified their fellowship subspecialty before the 3rd year of residency with only 5.7% selecting pediatric radiology. Overall, 18.2% of survey respondents favored academic practice compared to 40% in the pediatric radiology subgroup. Fellowship choices were most strongly based on area of strong personal interest, marketability and area of strong personal knowledge, while the pediatric radiology subgroup emphasized area of strong personal interest, increased interaction with other physicians and enjoyable residency rotations. The pediatric radiology subgroup believed their impact on patient care was more significant than other subspecialties. Pediatric radiology job opportunities were thought to be more limited, geographically confining, and to have lower salaries than other subspecialties. More flexible job opportunities and higher demand were identified as factors needing to change before a resident would consider a pediatric radiology career. CONCLUSION: The influence on fellowship selection is multifactorial. By emphasizing the favorable job market and marketability of pediatric radiology in all practice types/geographic locations, correcting perceived salary gaps and stressing the impact on patient care as early as medical school, the number of residents choosing a career in pediatric radiology may grow.

Diagnostic accuracy of non-contrast magnetic resonance enterography in detecting active bowel inflammation in pediatric patients with diagnosed or suspected inflammatory bowel disease to determine necessity of gadolinium-based contrast agents.

BACKGROUND: Pediatric patients with inflammatory bowel disease (IBD) are at increased risk of gadolinium deposition given the potential need for multiple contrast-enhanced magnetic resonance enterography (MRE) exams over their lifetime. OBJECTIVE: To determine whether gadolinium-based contrast agents are necessary in assessing active bowel inflammation on MRE in pediatric patients with known or suspected IBD. MATERIALS AND METHODS: We conducted a retrospective study of 77 patients (7-18 years; 68.8% male) with known (n=58) or suspected (n=19) IBD and endoscopy with biopsy performed within 30 days of MRE without and with contrast evaluated bowel and non-bowel findings. During three visual analysis sessions, two radiologists reviewed pre-, post-, and pre-/post-contrast MRE images. A third radiologist independently reviewed 27 studies to assess inter-reader reliability. We used Cohen kappa (κ), Fleiss kappa, (κF), McNemar test, and sensitivity and specificity to compare MRE readings to combined endoscopic/histopathological findings (the reference standard). RESULTS: The pre- and pre-/post-contrast-enhanced MRE vs. combined endoscopic/histopathological results had moderate agreement (85.7%; κ 0.713, P<0.001; P-value 0.549). Compared to combined endoscopy/histopathology, pre- vs. pre-/post-contrast sensitivity (67%, confidence interval [CI] 0.53-0.79 vs. 67%, CI 0.53-0.79) and specificity (80%, CI 0.59-0.92 vs. 68%, CI 0.46-0.84) varied little (κ 0.42, P<0.001 and κ 0.32, P=0.003, respectively). The three readers had moderate agreement (85.2%; κ 0.695, P=0.001; P-value 0.625). More penetrating complications were identified following contrast administration (P-value 0.04). CONCLUSION: Use of a contrast agent does not improve the detection of active inflammation in the terminal ileum and colon compared to non-contrast MRE, although use of a contrast agent does aid in the detection of penetrating disease.

Rhabdoid tumor: an aggressive renal medullary tumor of childhood.

We present a case of a renal rhabdoid tumor in a 2-month-old girl. Rhabdoid tumors are rare primary renal tumors in children, but they have characteristic features--medullary sinus invasion and subcapsular fluid collections--which enable a specific diagnosis. The classic imaging characteristics of this tumor compared to other more common primary pediatric renal tumors will be reviewed.

Phosphaturic mesenchymal tumor of the tibia with oncogenic osteomalacia in a teenager.

Phosphaturic mesenchymal tumor is an uncommon cause of a paraneoplastic syndrome that can be associated with osteogenic osteomalacia. This tumor most commonly occurs in middle-aged men and women. We report a rare case of a phosphaturic mesenchymal tumor in a 16-year-old girl with multiple fractures as a result of severe osteoporosis. CT and MRI showed a mass arising from the tibia.

FGFR3-related condition: a skeletal dysplasia with similarities to thanatophoric dysplasia and SADDAN due to Lys650Met.

Mutations in the fibroblast growth factor receptor 3 (FGFR3) gene account for six related skeletal dysplasia conditions: achondroplasia, hypochondroplasia, thanatophoric dysplasia types 1 and 2, SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans), and platyspondylic lethal skeletal dysplasia, San Diego type. This group of disorders has very characteristic clinical and radiologic features, which distinguish them from other skeletal dysplasias. They display a spectrum of severity in the skeletal findings, ranging from relatively mild hypochondroplasia to lethal thanatophoric dysplasia. We report a patient who has the missense FGFR3 mutation, Lys650Met, previously reported in association only with SADDAN, who exhibits some findings similar to both thanatophoric dysplasia (types 1 and 2) in addition to those findings characteristic of SADDAN.

Extracardiac applications of MR blood pool contrast agent in children.

Magnetic resonance (MR) angiography has significantly reduced the need for diagnostic conventional angiography and is preferred over CT angiography in children because of its lack of ionizing radiation. The availability of gadofosveset trisodium (the only clinically approved blood pool MR contrast agent) has led to an increase in applications of MR for vascular imaging and an improvement in diagnostic quality of MR angiography. Gadofosveset is a gadolinium-based contrast agent that binds reversibly to albumin, resulting in increased paramagnetic effect and longer intravascular residence. This allows for high-resolution arterial and venous MR angiography, assessment of flow characteristics of vascular malformations, dynamic vascular imaging, and multi-station imaging with a single low-dose gadolinium contrast injection. The purpose of this pictorial essay is to facilitate understanding of the kinetics and safety profile of gadofosveset trisodium, discuss technical aspects of imaging, and illustrate advantages and extracardiac applications in pediatric body imaging.

Neurofibromatosis 1 vasculopathy manifesting as a peripheral aneurysm in an adolescent.

Arterial vasculopathy is a well-recognized but uncommon manifestation of neurofibromatosis type 1 (NF-1). It can manifest as stenoses, aneurysms or arteriovenous malformations. NF-1 vasculopathy typically involves the aorta, visceral arteries or carotid-vertebral circulation. Aortic and visceral vasculopathy typically presents as stenotic lesions, while aneurysms have been reported primarily in the subclavian/vertebral arteries. Aneurysms of the peripheral/extremity arteries are an extremely rare complication of NF-1 that may present as a mass or spontaneous rupture. We present the case of a teenage boy with an arm mass secondary to an aneurysm. We hope this case will increase recognition of the variable clinical manifestations of NF-1 vasculopathy among radiologists.

Thymoma with osseous metaplasia in an adolescent.

A 13-year-old girl was incidentally found to have a partially calcified anterior mediastinal mass during the work-up for a left humeral lesion. The resected specimen demonstrated a lymphocyte predominant World Health Organization type B1 thymoma with nodules of metaplastic bone consistent with osseous metaplasia. In addition, she had multiple osteochondromas, a periosteal chondroma of the humerus, a metaplastic osseous pseudotumor of the thigh, and other benign-appearing sclerotic foci, all manifestations of what is likely an autosomal dominant disorder.

Perspective: Mandatory Radiology Education for Medical Students.

Radiology education of medical students is increasingly important given the intersection of radiology with virtually all medical specialties and integral role of imaging in modern patient care. Yet radiology education requirements in US medical schools are variable with only a minority of schools requiring a clerkship in radiology. When required, the radiology curriculum is often limited to anatomy courses in the preclinical years or partially incorporated into required core clerkships and often taught by nonradiologists. Given the growing mandate for value-based care and emphasis on patient outcomes, medical students require better imaging education, both interpretive and non-interpretative skills. They should be taught how to apply appropriateness criteria for exam ordering and the relative costs of different imaging modalities given the economic implications of imaging overutilization. Medical students should also be educated regarding imaging safety considerations. In addition, they must learn the radiologist's role as consultant to assure appropriate ordering of imaging studies, oversight for performance of diagnostic exams and image-guided procedures, interpretation of studies, and communication of results. Increasing radiologist teaching and engagement with medical students also has the potential to improve diversity and inclusivity in radiology by increasing interest in the specialty as physicians who identify as underrepresented minorities (URMs) are more likely to practice in underserved areas and with underserved populations thus addressing healthcare disparities and improving access to healthcare for those patient populations. Medical schools should support preclinical and clinical curricula that is designed and taught by radiologists.

Use of Artificial Intelligence in Radiology: Impact on Pediatric Patients, a White Paper From the ACR Pediatric AI Workgroup.

In this white paper, the ACR Pediatric AI Workgroup of the Commission on Informatics educates the radiology community about the health equity issue of the lack of pediatric artificial intelligence (AI), improves the understanding of relevant pediatric AI issues, and offers solutions to address the inadequacies in pediatric AI development. In short, the design, training, validation, and safe implementation of AI in children require careful and specific approaches that can be distinct from those used for adults. On the eve of widespread use of AI in imaging practice, the group invites the radiology community to align and join Image IntelliGently (www.imageintelligently.org) to ensure that the use of AI is safe, reliable, and effective for children.