Body weight-based iodinated contrast immersion timing for human fetal postmortem microfocus computed tomography

Objectives The aim of this study was to evaluate the length of time required to achieve full iodination using potassium tri-iodide as a contrast agent, prior to human fetal postmortem microfocus computed tomography (micro-CT) imaging. Methods Prospective assessment of optimal contrast iodination was conducted across 157 human fetuses (postmortem weight range 2-298 g; gestational age range 12-37 weeks), following micro-CT imaging. Simple linear regression was conducted to analyse which fetal demographic factors could produce the most accurate estimate for optimal iodination time. Results Postmortem body weight (r2 = 0.6435) was better correlated with iodination time than gestational age (r2 = 0.1384), producing a line of best fit, y = [0.0304 × body weight (g)] − 2.2103. This can be simplified for clinical use whereby immersion time (days) = [0.03 × body weight (g)] − 2.2. Using this formula, for example, a 100-g fetus would take 5.2 days to reach optimal contrast enhancement. Conclusions The simplified equation can now be used to provide estimation times for fetal contrast preparation time prior to micro-CT imaging and can be used to manage service throughput and parental expectation for return of their fetus. Advances in knowledge A simple equation from empirical data can now be used to estimate preparation time for human fetal postmortem micro-CT imaging

Artificial intelligence for radiological paediatric fracture assessment: a systematic review

BACKGROUND: Majority of research and commercial efforts have focussed on use of artificial intelligence (AI) for fracture detection in adults, despite the greater long-term clinical and medicolegal implications of missed fractures in children. The objective of this study was to assess the available literature regarding diagnostic performance of AI tools for paediatric fracture assessment on imaging, and where available, how this compares with the performance of human readers. MATERIALS AND METHODS: MEDLINE, Embase and Cochrane Library databases were queried for studies published between 1 January 2011 and 2021 using terms related to 'fracture', 'artificial intelligence', 'imaging' and 'children'. Risk of bias was assessed using a modified QUADAS-2 tool. Descriptive statistics for diagnostic accuracies were collated. RESULTS: Nine eligible articles from 362 publications were included, with most (8/9) evaluating fracture detection on radiographs, with the elbow being the most common body part. Nearly all articles used data derived from a single institution, and used deep learning methodology with only a few (2/9) performing external validation. Accuracy rates generated by AI ranged from 88.8 to 97.9%. In two of the three articles where AI performance was compared to human readers, sensitivity rates for AI were marginally higher, but this was not statistically significant. CONCLUSIONS: Wide heterogeneity in the literature with limited information on algorithm performance on external datasets makes it difficult to understand how such tools may generalise to a wider paediatric population. Further research using a multicentric dataset with real-world evaluation would help to better understand the impact of these tools

A novel radiographic scoring system for growth abnormalities and structural change in children with juvenile idiopathic arthritis of the hip

Background: Approximately 20\u201350% of children with juvenile idiopathic arthritis (JIA) have hip involvement within 6 years of diagnosis. Scoring systems for hip-related radiographic changes are lacking. Objective: To examine precision of potential radiographic variables and to suggest a scoring system. Materials and methods: We reviewed a set of 75 pelvic radiographs from 75 children with JIA hip involvement across two European centres. We assessed findings of (1) destructive change and (2) growth abnormality, according to a pre-defined scoring system. All radiographs were scored independently by two sets of radiologists. One set scored the radiographs a second time. We used kappa statistics to rate inter- and intra-observer variability. Results: Assessment of erosions of the femoral head, femoral neck and the acetabulum showed moderate to good agreement for the same reader (kappa of 0.5\u20130.8). The inter-reader agreement was, however, low (kappa of 0.1\u20130.3). There was moderate to high agreement for the assessment of femoral head flattening (kappa of 0.6\u20130.7 for the same reader, 0.3\u20130.7 between readers). Joint space narrowing showed moderate to high agreement both within and between observers (kappa of 0.4\u20130.8). Femoral neck length and width measurements, the centrum\u2013collum\u2013diaphysis angle, and trochanteric\u2013femoral head lengths were relatively precise, with 95% limits of agreement within 10\u201315% of the observer average. Conclusion: Several radiographic variables of destructive and growth abnormalities in children with hip JIA have reasonable reproducibility. We suggest that future studies on clinical validity focus on assessing only reproducible radiographic variables

Stresses and strains on the human fetal skeleton during development

Mechanical forces generated by fetal kicks and movements result in stimulation of the fetal skeleton in the form of stress and strain. This stimulation is known to be critical for prenatal musculoskeletal development; indeed, abnormal or absent movements have been implicated in multiple congenital disorders. However, the mechanical stress and strain experienced by the developing human skeleton in utero have never before been characterized. Here, we quantify the biomechanics of fetal movements during the second half of gestation by modelling fetal movements captured using novel cine-magnetic resonance imaging technology. By tracking these movements, quantifying fetal kick and muscle forces, and applying them to three-dimensional geometries of the fetal skeleton, we test the hypothesis that stress and strain change over ontogeny. We find that fetal kick force increases significantly from 20 to 30 weeks' gestation, before decreasing towards term. However, stress and strain in the fetal skeleton rises significantly over the latter half of gestation. This increasing trend with gestational age is important because changes in fetal movement patterns in late pregnancy have been linked to poor fetal outcomes and musculoskeletal malformations. This research represents the first quantification of kick force and mechanical stress and strain due to fetal movements in the human skeleton in utero, thus advancing our understanding of the biomechanical environment of the uterus. Further, by revealing a potential link between fetal biomechanics and skeletal malformations, our work will stimulate future research in tissue engineering and mechanobiology

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Hermes and the Tortoise: A Prelude to Cult

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High resolution isotropic diffusion imaging in post-mortem neonates:a feasibility study

OBJECTIVE: To investigate the potential of advanced diffusion imaging in Post-Mortem MRI (PMMR) at 3T.  Methods: We acquired PMMR brain and body imaging in 12 neonates, mean gestational age 33.4 weeks (range 29-37 weeks) at 3T and 1.5T. Head and body diffusion imaging at 1.5T using bipolar diffusion encoding and single-shot echo-planar imaging (EPI) for acquisition (TE 96ms; TR 2700ms; voxel size 1.8x1.8mm in-plane with slice thickness 5mm; b values of 500 and 1000 s/mm2 applied in three orthogonal directions; total acquisition time 2:12). A whole-body 3T diffusion imaging protocol using monopolar diffusion encoding and simultaneous multi-slice EPI acquisition with gradients applied in 12 uniformly distributed directions were obtained (TE 53.4ms; TR 5600ms; 1.8mm isotropic; multi-band factor 2; b-values of 250, 750, 1250 and 1750 s/mm2; acquisition time 2:09 for a single b-value,).  Results: There was significant improvement in image quality in multiband, multi-slice diffusion PMMR protocol. On visual assessment of image quality, 1.5T DWI scored poorly (mean 2.4 SD ± 0.47), and all 3T b values individually scored significantly higher (p < 0.001) apart from b = 250 which was not significantly different. CONCLUSION: Recent advances in diffusion sequences and hardware utilising higher field strengths and gradient performance allows whole-body diffusion PMMR imaging at high resolution with improved image quality compared to the current clinical approach. Advances in knowledge: We have demonstrated feasibility of a multi-slice, multi-band quantitative diffusion imaging sequence in the perinatal post-mortem setting. This will allow more detailed and quantitative clinical PMMR investigations using diffusion MRI in the future

Coronavirus disease 2019 (COVID-19) in children: a systematic review of imaging findings

BACKGROUND COVID-19 is a novel coronavirus infection that can cause a severe respiratory illness and has been declared a pandemic by the World Health Organization (WHO). Because children appear to be less severely affected than adults, their imaging appearances have not been extensively reported. OBJECTIVE To systematically review available literature regarding imaging findings in paediatric cases of COVID-19. MATERIALS AND METHODS We searched four databases (Medline, Embase, Cochrane, Google Scholar) for articles describing imaging findings in children with COVID-19. We included all modalities, age <18 years, and foreign language articles, using descriptive statistics to identify patterns and locations of imaging findings, and their association with outcomes. RESULTS Twenty-two articles were included, reporting chest imaging findings in 431 children, of whom 421 (97.7%) underwent CT. Criteria for imaging were lacking. At diagnosis, 143/421 (34.0%) had a normal CT. Abnormalities were more common in the lower lobes and were predominantly unilateral. The most common imaging pattern was ground-glass opacification (159/255, 62.4%). None of the studies described lymphadenopathy, while pleural effusions were rare (three cases). Improvement at follow-up CT imaging (3-15 days later) was seen in 29/100 (29%), remained normal in 25/100 (25%) and progressed in 9/100 (9%). CONCLUSION CT chest findings in children with COVID-19 are frequently normal or mild. Lower lobes are predominantly affected by patchy ground-glass opacification. Appearances at follow-up remain normal or improve in the majority of children. Chest CT imaging adds little to the further management of the patient and should be reserved for severe cases or for identifying alternative diagnoses

Perinatal post mortem ultrasound (PMUS): a practical approach

Abstract Declining rates of consent for standard perinatal autopsy has led to a rise in interest for postmortem imaging as an alternative, non-invasive method for investigation of childhood and perinatal deaths. Whilst much interest has focussed on cross-sectional techniques such as postmortem CT (PMCT) or MRI (PMMR), other modalities including postmortem ultrasound (PMUS) have been shown to have reasonable diagnostic accuracy rates, with the added benefit of being more readily accessible and affordable. There is little published information or formal guidance available on preparation for postmortem perinatal ultrasound, views to be obtained and differentiating normal postmortem change from potential abnormalities. This article will focus on the role of perinatal postmortem ultrasound as an alternative imaging method for non-invasive autopsy, with emphasis on imaging technique, practical considerations and commonly encountered case examples