[Multislice thoracic CT scanner]. / Scanner thoracique multibarette.

The scanner, or computed tomography, is the reference imaging test for most thoracic diseases in both adults and children. It has gone through tremendously rapid technological progress over the last few years with the appearance of multirow (or multidetector or multislice) scanners. This technology currently provides volume acquisition of a child's thorax in 2-5 s. These technological advances are particularly useful for exploring airway diseases, largely because of the range of reconstruction possibilities (maximum and minimum intensity projection, volume rendering, virtual endoscopy), which offer advantageous perspectives in pediatrics. Multiplanar imaging and above all three-dimensional imaging provide a totally original analysis in space of the sometimes complex relations between vascular and airway structures, making it possible to understand certain extrinsic bronchial compression mechanisms more precisely. The present study briefly reviews the technical aspects of the thoracic scanner in children and illustrates its role today in volume CT in childhood thoracic diseases using clinical examples taken from our daily practice.

CT scan patterns of pulmonary alveolar proteinosis in children.

BACKGROUND: To study computed tomographic (CT) findings in children with pulmonary alveolar proteinosis (PAP) more extensively. OBJECTIVE: To describe the CT features at the time of diagnosis and after therapeutic broncho-alveolar lavage (BAL). MATERIALS AND METHODS: We retrospectively reviewed the CT scans of five children (aged 3 months to 4 years) examined because of incidental bronchitis (n = 1), disease in a sibling (n = 1) and relapsing fever, cough and dyspnoea (n = 3). Each patient had an initial CT scan. Two asymptomatic cases were not treated but were followed up by plain chest films. The other three had BAL and follow-up CT. RESULTS: Initial CT in all cases showed a diffuse reticulomicronodular pattern associated in three cases with posterior bilateral alveolar infiltrates. CT in the two asymptomatic patients remained unchanged or slightly improved without BAL. After BAL, a variable decrease of lung infiltrates was observed. CONCLUSIONS: Correlation between the extent of alveolar consolidation and severity of disease was found. Anatomical and pathological considerations allow us to consider that the classical reticulomicronodular pattern is not due to an interstitial infiltration but to alveoli filled with the abnormal material characteristic of PAP.

Cd1a-positive cells in bronchoalveolar lavage samples from children with Langerhans cell histiocytosis.

We evaluated CD1a-positive cells in bronchoalveolar lavage samples from children with Langerhans cell histiocytosis (LCH). All children with multifocal LCH and pulmonary symptoms scored higher than 5% (30.6% +/- 7.2%), whereas those with other lung disorders scored much less than 5%. In children with multifocal LCH, bronchoalveolar lavage fluid abnormalities can precede pulmonary symptoms. During chemotherapy the CD1a-positive cell count lends to decrease.

[Morphological and functional study of pulmonary arteries by MRI]. / Etude morphologique et fonctionnelle des artères pulmonaires par l'IRM.

This article presents an exhaustive review of MRI in the assessment of the pulmonary arteries (sequences, normal results, clinical signs of the main diseases). Its current preferential indications are: the study of the main pulmonary artery trunks (primary tumours, proximal embolism, caliber abnormalities, anatomical relations with central tumours), the assessment and post-treatment follow-up of pulmonary arterial malformations. Angio-MRI is currently being developed and, in the near future, should allow the reliable diagnosis of pulmonary embolism and will therefore be indicated alongside spiral computed tomography. MRI also allows functional assessment of the right circulation (measurements of circulatory velocity and flow rates). It should rapidly become an examination of choice in the haemodynamic follow-up of patient with pulmonary hypertension and transplant recipients and as an evaluation tool for new drugs.

Bronchopulmonary dysplasia: value of CT in identifying pulmonary sequelae.

OBJECTIVE: Pulmonary dysfunction is common in children who survive bronchopulmonary dysplasia. Chest radiographs are not satisfactory for the identification of the sequelae of bronchopulmonary dysplasia because, although they often show abnormalities, the abnormalities are usually minor and sometimes absent. We therefore assessed the value of CT for identifying the sequelae of bronchopulmonary dysplasia. MATERIALS AND METHODS: Twenty-three children (mean age, 4 years) who had survived neonatal bronchopulmonary dysplasia and had signs of chronic pulmonary dysfunction (recurrent episodes of coughing, wheezing, dyspnea, pneumonia, respiratory insufficiency) were examined with chest radiographs and high-resolution CT scans of the chest. Two reviewers qualitatively analyzed the chest radiographic and CT findings by describing the most consistently found lesions and their frequencies. RESULTS: The chest radiographs showed hyperexpansion in 17, hyperlucent areas in 11, and linear opacities in 10 of the 23 children. Pleural thickening was not observed, and four children had normal findings on chest radiographs. All 23 CT scans showed abnormalities, including multifocal areas of hyperaeration, well-defined linear opacities, and triangular subpleural opacities with an external base and an internal apex. In 20 of 23 children, all three abnormalities were present. For the three other children, two of these three abnormalities were found. No bronchiectasis was observed in any of the cases. CONCLUSION: Lesions in survivors of bronchopulmonary dysplasia with chronic pulmonary dysfunction are visualized better on CT scans than on chest radiographs. Importantly, CT findings of multifocal areas of hyperaeration, numerous linear opacities facing triangular subpleural opacities visible on several consecutive sections, and no bronchiectasis should suggest the presence of sequelae of bronchopulmonary dysplasia.

[Practical diagnostic approach to anomalies of the aortic arch. Apropos of 31 pediatric cases]. / Approche diagnostique pratique des anomalies des arcs aortiques. A propos de 31 cas pédiatriques.

This analysis of 31 cases of anomalies of the aortic arch has confirmed the predominance of subclavian retro-oesophageal arteries and double aortic arches (74% of cases). The age at which the first clinical signs presented was less than one year in 75% of cases. Respiratory signs predominated with recurrent bronchitis (16 cases) and bronchial congestion (9 cases). These signs were not specific for the type of aetiology and were characterised by their chronicity and recurrent nature. Inspiratory and expiratory stridor was found on 8 occasions and was very suggestive of the diagnosis. There was a frequent association of asthma and anomalies of the aortic arch in this series (13 cases) with 6 cases of atopic asthma in early childhood and 7 cases of asthma in infancy. The oesophago-gastroduodenal transit was the key diagnosis which enabled the vascular anomaly to be confirmed. There was, however, a failure on 5 occasions with 2 false negatives and 3 cases where the wrong type was suspected. Fibreoptic bronchoscopy enabled the topography to be established more precisely including the degree of compression (in 14 cases) and showed evidence of associated tracheomalacia in 7 cases. Nuclear magnetic resonance was very helpful, giving a better definition of the anatomical type and of the relationship of the vascular arch with the oesophago-tracheal axis. Broncho-fibroscopy and nuclear magnetic resonance make strong contributions towards the indications for operation.

Angioplasty of renal transplant artery stenosis in children.

Systemic hypertension after renal transplantation in children is frequent, occurring in 85% of the cases and may be the cause of severe neurologic complications. This can be due to multiple factors such as: rejection, recurrence of initial disease, steroid, etc. ... Among those factors, renal transplant artery stenosis (RTAS) must be identified as it may be cured by angioplasty. We report our experience in 18 children who had undergone angioplasty for RTAS. Angioplasty was performed under general anesthesia with 3F, 4F or 5F balloon catheters. Angioplasty was successful in 14 cases (77%) immediately (10 cases), progressively (2 cases) or after a successfully redilated recurrence (2 cases). Two of the 4 failures were due to technical problems, a successful surgical treatment was then performed. The 2 others failures were explained by a severe transplant rejection. The complications were rare: 1 femoral artery thrombosis and spasms of the intra renal arteries but without repercussion on the renal function. In our experience, angioplasty seems to be the treatment of choice in RTAS in children. However the indications must be carefully established taking in account other possible causes of hypertension in such patients.

[MRI of aortic arch anomalies in children. Initial results]. / IRM des anomalies des arcs aortiques chez l'enfant. Premiers résultats.

A prospective study by nuclear magnetic resonance in 7 infants with respiratory disorders and with a barium swallow suggestive of anomalies of the aortic arch was conducted. It allowed the definition of an investigation protocol including sedation, RF coil adapted to infants size, naso-gastric tube placement, thin MR sections. Sequences are T1 weighted with ECG gating in two perpendicular frontal oblique and transverse oblique planes determined on a scout sagittal MR acquisition. Precise determination of the anatomy of the vascular malformation and its relationship with the trachea and esophagus were obtained. After definition of the investigation protocol, MRI was found to be a very effective evaluation technique for aortic arch anomalies. It can be proposed as an alternative to preoperative digital angiography. Its indications remain to be defined in relation to the clinical features and the results of the chest X-ray and barium swallow.