Non-contrast-enhanced MR angiography using time-spin labelling inversion pulse technique for detecting crossing renal vessels in children with symptomatic ureteropelvic junction obstruction: comparison with surgical findings.

OBJECTIVES: Investigate the feasibility and evaluate the accuracy of non-contrast-enhanced MR angiography (NC-MRA) using time-spin labelling inversion pulse (time-SLIP)to identify crossing renal vessels (CRVs) in children requiring surgical treatment of ureteropelvic junction (UPJ) obstructionand compare to laparoscopic findings. MATERIALS AND METHODS: Nineteen children ranging from 6 to 16 years of age underwent NC-MRA using the time-SLIP technique before surgery. Two independent readers analysed the MRA images. Number of renal arteries and presence or absence of CRVs were identified and compared with surgicalfindings. Image quality was assessed, as well as the presence of CRVs and measurement of renal pelvis diameter. Intra and inter-reader agreement was calculated using Cohen's kappa coefficient and Bland-Altman plots. RESULTS: The overall image quality was fair or good in 88% of cases. NC-MRA demonstrated CRVs at the level of the obstruction in 10 children and no CRV in 9 children. All were confirmed intra-operatively except in one of the nine children. Sensitivity, specificity, NPV, PPV for predicting CRVs were 92%, 100%, 100% and 87.5%, respectively, for both readers. CONCLUSION: NC-MRA is a good alternative to contrast-enhanced MRA and CT scanning for identifying CRVs in children with symptomatic UPJ. KEY POINTS: • Time-SLIP technique offers acceptable imaging quality for identifying crossing renal vessel. • Time-SLIP technique is easy to apply to the renal MRA examination. • Time-SLIP technique is an alternative to contrast-enhanced MRA and CT scanning

MRI evaluation of the hydration status of non-pathological lumbar intervertebral discs in a pediatric population

Introduction The intervertebral disc (IVD) is made up of the annulus fibrosus (AF) and the nucleus pulposus (NP) – an inert hydrated complex. The ability of the IVD to deform is correlated to that of the NP and depends on its hydration. As the IVD ages, its hydration decreases along with its ability to deform. In adolescent idiopathic scoliosis, one of the etiological hypotheses pertains to the IVD, thus making its condition relevant for the diagnosis and monitoring of this pathology. Hypothesis IVD hydration depends on sex, age and spine level in an asymptomatic pediatric population. The corollary is data on a control group of healthy subjects. Material and methods A cohort of 98 subjects with normal spine MRI was enrolled; their mean age was 13.3 years. The disc volume and hydration of each IVD was evaluated on T2-weighted MRI sequences, using previously validated image processing software. This evaluation focused on the lumbar spine, from the thoracolumbar junction to the lumbosacral junction. It was assumed that IVD hydration was related to the ratio of NP and AF volumes. A mixed multivariate linear analysis was used to explore the impact of age, sex and spinal level on disc hydration. Results Disc hydration was higher overall in boys than in girls, but this difference was not significant. Hydration increased with age by +0.005 for each additional year (p = 0.0213). Disc hydration appears to be higher at the thoracolumbar junction than the lumbar spine, although this difference was not significant. Conclusion Through this MRI study, we established a database of non-pathological lumbar disc hydration as a function of age, sex and spinal segment along with 95% confidence intervals

Relevance of MRI for management of non-displaced lateral humeral condyle fractures in children

INTRODUCTION: The treatment for non-displaced (<2 mm displacement) fractures of the lateral humeral condyle in children is controversial. Most studies recommend non-surgical treatment. However, plain radiographs are not sufficient to evaluate extension of the fracture line through the articular cartilage. This explains the high frequency of secondary displacements and non-unions, despite well-conducted conservative treatment. We hypothesized that MRI could be used to analyse whether the fracture is complete or incomplete. This could help to determine whether surgical or conservative treatment is indicated. MATERIAL AND METHODS: This prospective study enrolled children being treated for a non-displaced (< 2 mm gap) fracture of the lateral humeral condyle. All patients were treated with a long-arm cast in the emergency room. An MRI was done later on without sedation. A specific protocol was used to reduce the duration of the examination. T2-weighted and proton density fat-saturated sequences were used. RESULTS: Twenty-seven patients were enrolled: 16 boys and 11 girls with a mean age of 5 years (2-10). The MRI was performed an average of 7 days (1-23) after the fracture. The MRI could not be interpreted in two cases because the child had moved during the examination. In the other 25 patients, the fracture was incomplete in 17 patients and complete in 8 patients. Two children had secondary displacement diagnosed 7 and 11 days after the fracture event. These two patients underwent open reduction and internal fixation. There was no correlation between patient age and the fracture being complete or incomplete. There were no cases of non-union. CONCLUSION: MRI appears to be a reliable method for determining whether the fracture line is complete or incomplete. It can be performed without sedation, even in children as young as 2 years of age. Use of an injury-specific MRI protocol reduces the length of the examination, thereby improving its performance. We recommend that it be used to analyse non-displaced fractures of the lateral humeral condyle in children

Imagerie actuelle des kystes du cholédoque

TOULOUSE3-BU Santé-Centrale (315552105) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Attracting psychologists to practice in rural Australia : the role of work values and perceptions of the rural work environment

Objective: To investigate whether psychologists' career/work values and perceptions of the rural work environment influence their intentions or choice to practise in a rural location beyond the effect of rural background. Design: Online, cross-sectional survey assessed rural background, work values and perceptions of the reinforcers available in rural and urban work environments. Participants: One hundred and eighty-nine first year psychology students (78.8% women) and 124 registered psychologists (84.7% women). Main Outcome Measure: Students' intention to practise in a rural location and psychologists' choice of practice location. Results: Rural environments were seen as offering psychologists less opportunity than urban environments to fulfil their need for lifestyle, prestige, management and scholarly pursuits, but more opportunity for service and autonomy. Practitioners and students who placed less value on prestige were more likely to have worked in a rural area or be intending to do so. High value of service was also a predictor of rural intentions. Perceptions that rural work environments offered opportunities for scholarly pursuits increased the odds that a psychologist had spent time practising in a rural area. Person-environment fit was not significant. Conclusions: Recruitment and retention strategies to address the shortage of mental health professionals in rural areas need to consider perceptions of the work environment and how to fulfil practitioners' work values.7 page(s

In vivo determination of homogenised mechanical characteristics of human tibia: application to the study of tibial torsion in vivo

Objective. The study presents a method allowing the in vivo homogenised characteristics of the tibiae of children to be assessed.Design. Studies have been performed on two groups of children: six normal children, aged from 5 to 16 yr, and on four children, aged from 8 to 11 yr with tibial deformities. We analysed the tibial transverse sections from CT scans performed on the left tibia of each child.Background. Most tibial torsion studies have only been based on geometrical parameters. Our study integrated mechanical and geometrical considerations.Methods. The finite element models and integration of mechanical properties were performed from CT scans. Then homogenised mechanical characteristics (tensile stiffness, flexural stiffness and torsional stiffness) were calculated.Results. The homogenised mechanical characteristics decrease between 20 to 80% of the tibial length. The values increased with age for both groups of children. Children with abnormalities seem to have values of tibial rigidities comparable with those of normal tibiae.Conclusions. By considering the mechanical and geometrical properties of the tibia in our study, we showed that the bone stiffness of children is not altered with torsional deformities

Long-Term Effects on Tibial Growth After Intraosseous Infusion: A Prospective, Radiographic Analysis

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