[Chest radiographs in infants hospitalized for acute bronchiolitis: real information or just irradiation?]. / La radiographie de thorax chez le nourrisson hospitalisé pour bronchiolite aiguë : réelle information ou simple irradiation ?

OBJECTIVE: To describe the chest radiographs of infants hospitalized for acute bronchiolitis and to assess whether patient management changed after radiography. STUDY DESIGN: All infants hospitalized in our pediatric unit with a first episode of acute bronchiolitis from October 2010 to March 2012 were included in the study. Infants with chronic disease or transferred from a pediatric intensive care unit were excluded. The following data were collected: sex, age, neonatal history, atopy, tobacco exposure, admission criteria, treatment, laboratory parameters, ultrasonography and its outcome, results of chest radiography on admittance, the reason for a second chest radiograph, change in management as a result of the radiograph. RESULTS: The study comprised 232 infants (median age 2.2 months, boys 56%, positive respiratory syncytial virus 73.4%). Among them, 227 children had a routine chest radiograph revealing distension and/or bronchial wall thickening (n=141, 62.4%), focal opacity (19.9%), or atelectasis (17.7%). This radiograph led to the prescription of antibiotics in six patients (2.6%) and allowed the diagnosis of vascular abnormality to be made in one case (0.4%). Thirty-five patients (15.4%) had a second chest radiograph during their hospitalization owing to oxygen dependency (n=21), respiratory distress (n=11), persistent fever (n=2), or no reason specified (n=1). Pneumonia (n=7) and/or atelectasis (n=15) were then found in 62.9%. Patient management (antibiotics, postural maneuvers) was modified in six patients (17.1%). CONCLUSIONS: Routine chest radiographs contribute only partially to the treatment of infants hospitalized for acute bronchiolitis. However, radiography is useful when the hospitalized child does not improve at the expected rate or if the disease is severe. The indication of chest radiography in infants hospitalized for acute bronchiolitis should be discussed on a case by a case basis.

[Management of fetal mediastinal shift: a practical approach]. / Conduite à tenir devant une déviation médiastinale fœtale: une approche pratique.

The purpose of this article is to review the technique of fetal chest ultrasound screening evaluation, the diagnostic work-up in the presence of fetal mediastinal shift and which ultrasound imaging features to look for. The first step in evaluating the fetal thorax is to confirm situs. Then, a median sagittal line is drawn from a four-chamber view to assist in spatial orientation followed by echotexture analysis of the structures of the thorax in the presence of mediastinal shift. We propose a systematic approach based on the direction of the mediastinal shift and echogenicity of the compressing hemithorax. When the hemithorax contralateral to the mediastinal shift is enlarged, which is the most frequent situation, diaphragmatic hernia and macrocystic congenital cystic adenomatoid malformation are the most likely etiologies when the mass is heterogeneous. Microcystic congenital cystic adenomatoid malformation, sometimes associated with sequestration, is the most frequent etiology when the mass is homogeneous. When the hemithorax ipsilateral to the mediastinal shift is small, which is less frequent, and the contralateral hemithorax is homogeneously isoechoic, then a diagnosis of lung hypoplasia-agenesis-aplasia should be considered.

[Pediatric thoracic spine radiographs: Comparison of two scintillators]. / Radiographies thoraciques pédiatriques: comparaison de deux détecteurs à mémoire.

PURPOSE: To compare image quality and radiation exposure from pediatric thoracic spine radiographs from two systems, one using a granular structure scintillator and another using a needle structure scintillator with 40% reduction of exposure. PATIENTS AND METHODS: Randomized prospective study of 296 patients divided into 2 groups of 5 weight categories from 4 to 60 kg. Standard technique parameters are used for granular structure scintillators with dose reduction of 40% applied for needle structure scintillators based on results from a phantom study. Image quality based on detectability of 8 anatomical structures for both types of scintillators was assessed by 6 blinded radiologists. Exposure was expressed by DLP. Results underwent statistical analysis. RESULTS: Overall, image quality was superior with corresponding dose reduction between 33-46% according to weight with needle structure scintillators. For the 4 lower weight categories, image quality was identical. CONCLUSION: With image quality at least equal, new needle structure scintillator units allow a dose reduction of about 40%.

[Radiography of scoliosis: comparative dosimetry between conventional technique and digital fluorography]. / Radiographie des scolioses: dosimétrie comparée entre la technique conventionnelle et la fluorographie numérique.

OBJECTIVE: Compare the irradiation delivered in conventional radiography and digital radiography by image intensifier during a scoliosis workup. PATIENTS AND METHODS: Our prospective randomized study included 105 patients, all of whom were identified according to sociodemographic parameters as well as criteria evaluating the quality of the full front spinal x-ray at PA incidence. The entry dose at the scapula and the exit dose in interorbital, thyroid, mammary, and hypogastric projection was measured by thermoluminescent dosimeters. RESULTS: The results of 71 girls and 28 boys, aged a mean 13.8 years with a mean weight of 47 kg were analyzed. At equal image quality, the entry dose was not significantly different between the two techniques; the mean exit dose reduction was 64% during digital acquisition. This reduction involved the interorbital (162%), mammary (43%), and thyroid (309%) regions. However, this system is more irradiating in the hypogastric region (34%). CONCLUSION: The dosimetric evaluation of the different imaging techniques used to explore the entirety of the spine should be part of radiologists' quality standard used to document their work and their choices.

[Systemic learning planification for residents during the 6-month pediatric radiology training]. / Planification systémique de l'apprentissage des internes pendant un semestre de radiopédiatrie.

Diagnostic Radiology and Medical Imaging residents of French University Hospitals benefit from a wide array of learning tools. However, the professors' clinical workload, lack of sufficient proper formal training, lack of practical applicability of existing standards, and absence of rigorous assessment during the specialized training, reduce their very good quality formation to the level of accidental learning. This study originates from the need to apply a systemic planification of learning activities to the French residents' formal training curriculum, such as the one originally designed and applied within the Quebec educational system. This presentation also benefits from the recent introduction of the CanMEDS 2000 objectives by the Royal College of Physicians and Surgeons of Canada, in order to design an adapted version for the professional and academic activities of French radiologists. Needless to say this work will respect the outlined systematic planning of any learning activity: learning requirements, definition of learning objectives, selection of learning methods, assessment of the participants' achievement of these objectives, and evaluation of the learning activity itself.

[Kidney trauma in children: state of the art medical imaging]. / Traumatisme du rein de l'enfant: bonnes pratiques en imagerie médicale.

Traumatic renal lesions have some particularities in the pediatric age group, especially for anatomic reasons. Imaging is very important for diagnosis and staging. Ultrasonography with Doppler is the first line examination performed in children and frequently allows initial diagnosis. From the Doppler-ultrasonographic results and the type of trauma, renal Computed Tomography (CT) is complementary performed. The association of these imaging techniques allows comprehensive work-up of traumatic renal lesions, and also of associated or pre-existing lesions. Conservative management is the rule in most cases. Interventional imaging techniques are sometimes used for therapeutic care of renal pedicular vascular lesions or lesions of the collecting system. Far from the traumatic event, imaging allows to follow up the morphologic and functional evolution of major renal lesions, in particular lesions of excretory renal ducts.

[Imaging of the pediatric pancreas: state of the art]. / Imagerie du pancréas de l'enfant en 2005.

The use of high frequency (7-12 MHz) transducers on state of the art US units equipped with Doppler imaging provides excellent evaluation of the pediatric pancreas that compares to other cross-sectional imaging techniques. The availability of multidetector CT imaging reduces the need for sedation but requires additional review of the indications and protocols to avoid unnecessary radiation exposure. Evaluation of pancreatitis and tumors remains the main indication. Advances in MR imaging and MRCP has lead to very good results in children. Storage diseases of the pancreas can be diagnosed at MRI. The length of the examinations, the need for sedation and the limited spatial resolution remain the main pitfalls of MR imaging of the pancreas in pediatric patients.

[Immature hemangiomas in infants: MR and Doppler-US imaging features]. / Sémiologie IRM et écho-Doppler des hémangiomes immatures du nourrisson: à propos de 12 cas.

PURPOSE: To determine the MR imaging features of immature hemangiomas. To discuss the value of MR imaging compared to Doppler ultrasonography (US). MATERIALS AND METHODS: We performed a retrospective study of clinical, Doppler US and MRI data of 12 immature hemangiomas in 11 children. The mean age was 2 months and 21 days. The mean clinical follow up was 22 months and 7 days. RESULTS: MRI was performed for non-diagnosed lesions (4 cases) or to further define lesion extension (8 cases). The lesions either involved the head and neck (8 cases) or the extremities (4 cases). At MR imaging, all immature hemangiomas corresponded to well defined homogeneous T2W hyperintense masses. On T1-weighted images, 11 immature hemangiomas were isointense with intense homogeneous enhancement. Eleven tumors contained linear low signal intensity flow voids. Ten lesions had superficial cutaneous and/or subcutaneous extension whereas 2 lesions had intra-muscular extension. At Doppler US, immature hemangiomas were highly vascularized masses, with well defined margins, often compressibles, homogeneous isoechoic or heterogeneous with nodular hypoechoic foci, relative to subcutaneous fat. A diagnosis of immature hemangioma was confirmed either by pathology (2 cases) or clinical follow up (10 cases). CONCLUSION: In our study, the MR imaging features of immature hemangiomas were reproducible and similar to reports from the literature. MRI is a useful tool to better define the extent of immature hemangiomas, which can be difficult to assess at US. The sensitivity and specificity of MR imaging for this pathology remain to be defined.

[Non-traumatic abdominal emergencies in paediatric practice]. / Les urgences abdominales non traumatiques de l'enfant.

Do advances in MR imaging and Computed Tomography have encroached upon the private territory of Ultrasound-Doppler imaging on paediatric practice? Do the enthusiasm promoted by the use of CT on non traumatic acute abdomen in adult has contaminated the indomitable village of paediatric radiologist? Undoubtfully, Ultrasound-Doppler stayed the first imaging modality to perform. However, the habits are less crystallised than a few years ago. The goal of this article is to describe the ultrasound findings and the potential indications for MRI or CT in the major non traumatic abdominal paediatric emergencies.