Incidence and Risk Factors for Brown Adipose Tissue Uptake in PET Imaging in Pediatric Patients.

BACKGROUND: Positron emission tomography (PET) scans are used in disease diagnosis and evaluation for pediatric oncology patients. Brown adipose tissue (BAT) 18 F-fluorodeoxyglucose-PET uptake is reported in 35% to 47% of pediatric patients. Several risk factors may be associated with BAT uptake. OBJECTIVE: The aim was to determine the incidence and risk factors for BAT in pediatric patients using a consensus-based system and a novel grading scale. METHODS: A total of 285 PET scans in 154 patients were retrospectively reviewed for the presence of BAT from September 2015 through December 2016. A consensus review was done by 2 radiologists, who graded BAT on a 0 to 3 scale and assessed its impact on PET interpretation. RESULTS: The presence of moderate to severe BAT occurred in 11% of PET scans, and 6% of PETs had limited interpretation. Hodgkin lymphoma (n=53) patients had a 3.62-fold increased odds of moderate or severe BAT and a 6.59-fold increased odds of limited interpretation on PET imaging. CONCLUSION: The incidence of BAT was low but impacted radiologic interpretation when present. Further studies with a larger group of Hodgkin lymphoma patients are needed to explore the risk factors associated with moderate or severe BAT.

Magnetic resonance imaging findings following button battery ingestion.

BACKGROUND: Lithium button battery ingestions have been increasing in frequency since the early 2000s and can develop severe and sometimes fatal complications from caustic injury even after rapid battery removal. To aid in clinical decision-making, we began obtaining magnetic resonance imaging (MRI)/MR angiography in these patients. OBJECTIVE: Our goal was to review MRI/MR angiography imaging in button battery ingestion cases and compare with other imaging, clinical data and outcomes in these patients. MATERIALS AND METHODS: In this retrospective institutional-review-board-approved study, we reviewed all button battery ingestion cases with MRI from April 2012 to September 2018. Clinical data, endoscopic findings and all imaging studies were rereviewed. MRIs were evaluated for inflammation, blooming artifact and complications including vascular injury, tracheoesophageal fistula, esophageal perforation and spondylodiscitis, and compared to endoscopy, esophagram and bronchoscopy. RESULTS: Twenty-three patients with button battery ingestions had a total of 51 MRI/MR angiograms. Seventy percent of the cohort was male with a median age of 2 years (range: 0.94-17 years). Severe complications were found in 48% of patients (11/23), including esophageal perforation (n=11), tracheoesophageal fistula (n=3) and spondylodiscitis (n=1). No patients had vascular injury. Cervical location of the battery was significantly associated with severe complications (10/11 cases). The length of the blooming artifact was greater than 2 cm in those with severe complications and, in most cases, <2 cm in those without severe complications. All complications were seen on initial screening MR exam with serial exams showing decreased inflammation. CONCLUSION: MRI/MR angiography can provide valuable information about complications, including esophageal perforation, tracheoesophageal fistula and spondylodiscitis. Decreasing inflammation surrounding the esophagus and vasculature is believed to be clinically reassuring and aids in managing button battery ingestion patients.

Feasibility and Accuracy of Fast MRI Versus CT for Traumatic Brain Injury in Young Children.

BACKGROUND: Computed tomography (CT) is commonly used for children when there is concern for traumatic brain injury (TBI) and is a significant source of ionizing radiation. Our objective was to determine the feasibility and accuracy of fast MRI (motion-tolerant MRI sequences performed without sedation) in young children. METHODS: In this prospective cohort study, we attempted fast MRI in children <6 years old who had head CT performed and were seen in the emergency department of a single, level 1 pediatric trauma center. Fast MRI sequences included 3T axial and sagittal T2 single-shot turbo spin echo, axial T1 turbo field echo, axial fluid-attenuated inversion recovery, axial gradient echo, and axial diffusion-weighted single-shot turbo spin echo planar imaging. Feasibility was assessed by completion rate and imaging time. Fast MRI accuracy was measured against CT findings of TBI, including skull fracture, intracranial hemorrhage, or parenchymal injury. RESULTS: Among 299 participants, fast MRI was available and attempted in 225 (75%) and completed in 223 (99%). Median imaging time was 59 seconds (interquartile range 52-78) for CT and 365 seconds (interquartile range 340-392) for fast MRI. TBI was identified by CT in 111 (50%) participants, including 81 skull fractures, 27 subdural hematomas, 24 subarachnoid hemorrhages, and 35 other injuries. Fast MRI identified TBI in 103 of these (sensitivity 92.8%; 95% confidence interval 86.3-96.8), missing 6 participants with isolated skull fractures and 2 with subarachnoid hemorrhage. CONCLUSIONS: Fast MRI is feasible and accurate relative to CT in clinically stable children with concern for TBI.

Button Battery Powered Fidget Spinners: A Potentially Deadly New Ingestion Hazard for Children.

Toys entering the marketplace may have unrecognized hazard risks until data on injury become known. The fidget spinner is a new popular toy mass marketed to children and is primarily sold without warning labels. The US Consumer Product Safety Commission has recently issued a formal statement on potential safety concerns related to ingestion of the toy parts and other hazards. Button batteries within this toy pose the greatest danger to children as ingestion can lead to lethal injury. We report 2 cases of children who swallowed a button battery from a fidget spinner, causing severe esophageal injury. Various aspects of this type of ingestion important for clinicians to be aware of are reviewed.

CT outperforms radiographs at a comparable radiation dose in the assessment for spondylolysis.

BACKGROUND: Lumbar spondylolysis, a unilateral or bilateral fracture at pars interarticularis, is a common cause of low back pain in children. The initial imaging study in the diagnosis of lumbar spondylolysis has historically been lumbar spine radiographs; however, radiographs can be equivocal or false-negative. Definitive diagnosis can be achieved with computed tomography (CT), but its use has been limited due to the dose of ionizing radiation to the patient. OBJECTIVE: By limiting the z-axis coverage to the relevant anatomy and optimizing the CT protocol, we are able to provide a definitive diagnosis of fractures of the pars interarticularis at comparable or lower radiation dose than commonly performed lumbar spine radiographs. As there is no gold standard for the diagnosis of spondylolysis besides surgery, we compared interobserver agreement and degree of confidence to determine which modality is preferable. MATERIALS AND METHODS: Sixty-two patients with low back pain ages 5-18 years were assessed for the presence of spondylolyis. Forty-seven patients were evaluated by radiography and 15 patients were evaluated by limited field-of-view CT. Both radiographic and CT examinations were assessed anonymously in random order for the presence or absence of spondylolyisis by six raters. Agreement was assessed among raters using a Fleiss Kappa statistic for multiple raters. RESULTS: CT provided a significantly higher level of agreement among raters than radiographs (P < 0.001). The overall Kappa for rater agreement with radiographs was 0.24, 0.34 and 0.40 for 2, 3 or 4 views, respectively, and 0.88 with CT. CONCLUSION: Interobserver agreement is significantly greater using limited z-axis coverage CT when compared with radiographs. Radiologist confidence improved significantly with CT compared to radiographs regardless of the number of views.