Post-mortem skeletal survey (PMSS) versus post-mortem computed tomography (PMCT) for the detection of corner metaphyseal lesions (CML) in children.

OBJECTIVES: Corner metaphyseal lesions (CMLs) are specific for child abuse but challenging to detect on radiographs. The accuracy of CT for CML detection is unknown. Our aim was to compare diagnostic accuracy for CML detection on post-mortem skeletal surveys (PMSS, plain radiography) versus post-mortem CT (PMCT). METHODS: A 10-year retrospective review was performed at a children's hospital for patients having PMSS, PMCT and histopathological correlation (reference standard) for suspected CMLs. Twenty-four radiologists independently reported the presence or absence of CMLs in all cases in a blinded randomised cross-over design across two rounds. Logistic regression models were used to compare accuracy between modalities. RESULTS: Twenty CMLs were reviewed for each of the 10 subjects (200 metaphyses in all). Among them, 20 CMLs were confirmed by bone histopathology. Sensitivity for these CMLs was significantly higher for PMSS (69.6%, 95% CI 61.7 to 76.7) than PMCT (60.5%, 95% CI 51.9 to 68.6). Using PMSS for detection of CMLs would yield one extra correct diagnosis for every 11.1 (95% CI 6.6 to 37.0) fractured bones. In contrast, specificity was higher on PMCT (92.7%, 95% CI 90.3 to 94.5) than PMSS (90.5%, 95% CI 87.6 to 92.8) with an absolute difference of 2.2% (95% CI 1.0 to 3.4, p < 0.001). More fractures were reported collectively by readers on PMSS (785) than on PMCT (640). CONCLUSION: PMSS remains preferable to PMCT for CML evaluation. Any investigation of suspected abuse or unexplained deaths should include radiographs of the limbs to exclude CMLs. CLINICAL RELEVANCE STATEMENT: In order to avoid missing evidence that could indicate child abuse as a contributory cause for death in children, radiographs of the limbs should be performed to exclude CMLs, even if a PMCT is being acquired. KEY POINTS: • Corner metaphyseal lesions (CMLs) are indicative for abuse, but challenging to detect. Skeletal surveys (i.e. radiographs) are standard practice; however, accuracy of CT is unknown. • Sensitivity for CML detection on radiographs is significantly higher than CT. • Investigation of unexplained paediatric deaths should include radiographs to exclude CMLs even if CT is also being performed.

Artificial intelligence in paediatric radiology: Future opportunities.

Artificial intelligence (AI) has received widespread and growing interest in healthcare, as a method to save time, cost and improve efficiencies. The high-performance statistics and diagnostic accuracies reported by using AI algorithms (with respect to predefined reference standards), particularly from image pattern recognition studies, have resulted in extensive applications proposed for clinical radiology, especially for enhanced image interpretation. Whilst certain sub-speciality areas in radiology, such as those relating to cancer screening, have received wide-spread attention in the media and scientific community, children's imaging has been hitherto neglected.In this article, we discuss a variety of possible 'use cases' in paediatric radiology from a patient pathway perspective where AI has either been implemented or shown early-stage feasibility, while also taking inspiration from the adult literature to propose potential areas for future development. We aim to demonstrate how a 'future, enhanced paediatric radiology service' could operate and to stimulate further discussion with avenues for research.

Ligamentum arteriosum calcification on paediatric postmortem computed tomography.

BACKGROUND: Ligamentum arteriosum calcification may be a normal finding in some children, although the frequency has not been well described. OBJECTIVE: To estimate the frequency of ligamentum arteriosum calcification in children at postmortem imaging. MATERIALS AND METHODS: We conducted a single-centre retrospective review of paediatric postmortem CT and chest radiographic imaging over a 6-year period (January 2012 to December 2018). Two independent reviewers assessed the presence of calcification on imaging. We calculated descriptive statistical analysis of ligamentum arteriosum calcification frequency and association with age and gender. RESULTS: During the study period, 220 children underwent whole-body postmortem CT and 182 underwent radiographic imaging. The frequency was higher on postmortem CT than plain radiographs (67/220, 30.5% vs. 3/182, 1.6%) and was highest in children ages 1-7 years (53.6-66.7%), with gradual reduction in frequency in older children, and none in children older than 12 years. There was no gender predilection. CONCLUSION: In the postmortem setting, ligamentum arteriosum calcification is a common finding in children <8 years of age. It can be better identified on postmortem CT than chest radiographs. Radiologists new to reporting postmortem paediatric CT studies should recognise this as a common normal finding to avoid unnecessary further investigations at autopsy.

Diagnostic Accuracy of Postmortem CT of Children: A Retrospective Single-Center Study.

OBJECTIVE. The objective of our study was to determine the diagnostic accuracy of postmortem CT in children compared with standard autopsy. MATERIALS AND METHODS. This single-center retrospective study reviewed un-enhanced whole-body postmortem CT examinations of children less than 16 years old with corresponding autopsy reports irrespective of the clinical indication for referral for postmortem CT. Perinatal deaths were excluded. Postmortem CT was reported by experienced postmortem radiologists who were blinded to autopsy findings, with the primary outcome being concordance for the main pathologic diagnosis or findings leading to a cause of death. Autopsy performed by pediatric pathologists was the reference standard. RESULTS. One hundred thirty-six patients (74 [54.4%] male and 62 [45.6%] female patients) were included. The mean age of the 136 patients was 2 years 1 month (range, 2 days-14.7 years). A cause of death at autopsy was found for 77 of the 136 (56.6%) patients. Postmortem CT depicted a correct cause of death in 55 of 77 (71.4%) patients; (55/136 overall [40.4%]), with the majority attributable to traumatic brain or body injuries. For major pathologic findings, diagnostic accuracy rates were a sensitivity of 71.4% (95% CI, 60.5-80.3%), specificity of 81.4% (95% CI, 69.6-89.3%), positive predictive value of 83.3% (95% CI, 72.6-90.4%), negative predictive value of 68.6% (95% CI, 57.0-78.2%), and concordance rate of 75.7% (95% CI, 67.9-82.2%). The sensitivity of postmortem CT versus autopsy was highest for intracranial (75.6%; 95% CI, 60.7-86.2%) and musculoskeletal (98.4%; 95% CI, 91.4-99.7%) abnormalities and lowest for cardiac (31.3%; 95% CI, 14.2-55.6%) and abdominal (53.8%; 95% CI, 29.1-78.6%) findings. CONCLUSION. Postmortem CT gives an acceptable diagnostic concordance rate with autopsy of 71.4%, although identification of the cause of death overall was low at 40.4%. The highest accuracy rates were for intracranial and musculoskeletal abnormalities.

Microvascular Dysfunction in Dilated Cardiomyopathy: A Quantitative Stress Perfusion Cardiovascular Magnetic Resonance Study.

OBJECTIVES: This study sought to quantify myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) in dilated cardiomyopathy (DCM) and examine the relationship between myocardial perfusion and adverse left ventricular (LV) remodeling. BACKGROUND: Although regarded as a nonischemic condition, DCM has been associated with microvascular dysfunction, which is postulated to play a role in its pathogenesis. However, the relationship of the resulting perfusion abnormalities to myocardial fibrosis and the degree of LV remodeling is unclear. METHODS: A total of 65 patients and 35 healthy control subjects underwent adenosine (140 µg/kg/min) stress perfusion cardiovascular magnetic resonance with late gadolinium enhancement imaging. Stress and rest MBF and MPR were derived using a modified Fermi-constrained deconvolution algorithm. RESULTS: Patients had significantly higher global rest MBF compared with control subjects (1.73 ± 0.42 ml/g/min vs. 1.14 ± 0.42 ml/g/min; p < 0.001). In contrast, global stress MBF was significantly lower versus control subjects (3.07 ± 1.02 ml/g/min vs. 3.53 ± 0.79 ml/g/min; p = 0.02), resulting in impaired MPR in the DCM group (1.83 ± 0.58 vs. 3.50 ± 1.45; p < 0.001). Global stress MBF (2.70 ± 0.89 ml/g/min vs. 3.44 ± 1.03 ml/g/min; p = 0.017) and global MPR (1.67 ± 0.61 vs. 1.99 ± 0.50; p = 0.047) were significantly reduced in patients with DCM with LV ejection fraction ≤35% compared with those with LV ejection fraction >35%. Segments with fibrosis had lower rest MBF (mean difference: -0.12 ml/g/min; 95% confidence interval: -0.23 to -0.01 ml/g/min; p = 0.035) and lower stress MBF (mean difference: -0.15 ml/g/min; 95% confidence interval: -0.28 to -0.03 ml/g/min; p = 0.013). CONCLUSIONS: Patients with DCM exhibit microvascular dysfunction, the severity of which is associated with the degree of LV impairment. However, rest MBF is elevated rather than reduced in DCM. If microvascular dysfunction contributes to the pathogenesis of DCM, then the underlying mechanism is more likely to involve stress-induced repetitive stunning rather than chronic myocardial hypoperfusion.

Transmission of Mycobacterium xenopi to a pet albino ferret (Mustela putorius furo) from a domestic aquarium.

A three-year-old ferret presented with a three-month history of rapid clinical deterioration necessitating euthanasia shortly after initial veterinary assessment. Postmortem PCR testing confirmed Mycobacterium xenopi which is most commonly identified in amphibians, reptiles and aquatic life. Infection of a captive-bred domestic ferret is highly unusual. A collaborative effort involving medical doctors, clinical veterinarians and veterinary pathologists investigated the potential sources of human-animal, animal-animal and environmental-animal M xenopi transmission. No human-animal or animal-animal risks were identified. As the affected ferret was the only ferret to have regular exposure to the owner's aquarium, a postmortem study of a dead guppy and aquarium water analysis were performed which confirmed mycobacteriosis. Although M xenopi was not specifically cultured, as a slow-growing organism, M xenopi may have been outgrown by more rapidly growing mycobacteria or Gram-positive bacilli present in the water. Thus, transmission of M xenopi via aquarium exposure was certainly plausible. This is the second documented case of M xenopi in a ferret and the first to determine a source of infection. This report highlights the previously recognised risk of mycobacterial exposure from aquaria and that caution is required before allowing domestic ferrets to have contact with potentially infected water reservoirs due to its fatal nature in this vulnerable species.