The radiology of chronic lung disease in children

Abstract

Chronic lung disease (CLD) in children represents a heterogeneous group of many distinct clinicopathological entities. The prevalence of CLD has increased in the past decade because of the more advanced and intensive respiratory support provided for compromised children and additionally the overall improved survival of preterm babies. The disorders which constitute CLD generally have a slow tempo of progression over many months or even years. The most common causes of CLD in children are cystic fibrosis (CF), and other causes of bronchiectasis (such as immunodeficiency, and in the third world, post-infective bronchiectasis, for example, measles), bronchopulmonary dysplasia (BPD) (or lung disease of prematurity), asthma, chronic gastro-oesophageal reflux/aspiration pneumonitis, and constrictive obliterative bronchiolitis.

Figure 2

Chest radiographs in a child showing the serial changes of cystic fibrosis at 6 months, 5 years, and 10 years of age. There is progressive overinflation of the lungs with extensive bilateral bronchiectasis, particularly affecting the collapsed right upper lobe, where there is tubular dilatation of grossly abnormal bronchi.

Figure 3

HRCT in a teenager with end stage cystic fibrosis shows mosaic attenuation, dilatation, and wall thickening of the bronchi, mucus within bronchi, and terminal branches with tree-in-bud sign (arrow). On expiration (right) there is accentuation of the mosaic pattern, confirming small airways obstruction.

Figure 4

Chest radiograph showing mild bronchial thickening in a child with cystic fibrosis who had disproportionately severe respiratory functional impairment. VQ scans showed numerous matched ventilation and perfusion defects, explaining the child's clinical status.

Figure 6

Inspiratory (upper) and expiratory (lower) scans in a child with constrictive obliterative bronchiolitis showing bronchiolectasis with mucus plugging at the centrilobular bronchi and mosaic attenuation due to reflex vasoconstriction which is more marked on the expiratory lower scans.

Figure 7

Spiral and HRCT in a child with unexplained respiratory distress. There are diffuse airway and interstitial changes with peripheral pulmonary fibrosis, best appreciated on HRCT (lower images) over spiral CT (upper images). A barium swallow showed gross gastro-oesophageal reflux and aspiration into the lungs. Lung biopsy confirmed the presence of numerous fat laden macrophages consistent with the diagnosis of aspiration pneumonitis and subsequent bronchiectasis pulmonary fibrosis.

Figure 1

HRCT slice in a child with bronchiectasis shows bronchial dilatation with mild bronchial wall thickening (large airways disease), as well as almost globally hypoattenuating lung parenchyma and associated hypovascularity (small airways disease).

Figure 5

HRCT in a child born prematurely who had been in intensive care over a long period. There are features of bronchopulmonary dysplasia: widespread mosaic attenuation (corresponding to areas of air trapping on subsequent expiratory scan) and architectural distortion.