title: Thoracic CT in pediatric patients with difficult-to-treat asthma.
abstract: OBJECTIVE
  . The aim of this study was to establish objective, simple criteria for bronchial wall thickening in children with difficult-to-treat asthma.
  
  
  METHODS
  . Bronchial sections were counted at five levels in both lungs and at three levels in the right lung on high-resolution CT and plotted against lung function. Findings from 27 children with persistent symptoms of asthma (mean age, 11.4 years; SD, +/-3.1 years) that were severe (group A, n = 15) or moderate (group B, n = 12) were compared with findings from 21 control subjects (mean age, 10.8 years; SD, +/-3.0 years) using the Student's t test, analysis of variance, and Dunn-Bonferroni test.
  
  
  RESULTS
  . A bronchial wall thickening score based on the number of visible bronchi at three levels (three-level score) proved to be as valuable as and simpler to obtain than a score based on the number of bronchi at five levels (five-level score). The three-level scores for groups A and B were similar (mean +/- SD, 16.8 +/- 4.2 vs 18.4 +/- 3.4, respectively; p = not significant), but these scores were significantly higher than those for the control subjects (mean +/- SD, 8.2 +/- 3.4, respectively; p < 0.001). There was no correlation between the three-level score and forced expiratory volume in 1 sec or forced expiratory flow between 25% and 75% of forced vital capacity. In contrast with adults with severe asthma, our pediatric patients with difficult-to-treat asthma did not have CT evidence of mucoid impaction, emphysema, areas of hyperlucency, bronchiectasis, or sequellar line shadows.
  
  
  CONCLUSIONS
  . Bronchial wall thickening visible on high-resolution CT may constitute an additional criterion of asthma severity in children. CT evidence of bronchial wall thickening might help to identify patients with a higher risk of airway remodeling.
authors.affiliation: Service de Pneumologie et d'Allergologie Pédiatriques, Hôpital Necker Enfants Malades, 149 rue de Sèvres, 75015 Paris, France.
authors.forename: Valentine
authors.initials: V
authors.lastname: Marchac
authors.forename: Sophie
authors.initials: S
authors.lastname: Emond
authors.forename: Tania
authors.initials: T
authors.lastname: Mamou-Mani
authors.forename: Christine
authors.initials: C
authors.lastname: Le Bihan-Benjamin
authors.forename: Muriel
authors.initials: M
authors.lastname: Le Bourgeois
authors.forename: Jacques
authors.initials: J
authors.lastname: De Blic
authors.forename: Pierre
authors.initials: P
authors.lastname: Scheinmann
authors.forename: Francis
authors.initials: F
authors.lastname: Brunelle
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use; D001249:Asthma / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D001980:Bronchi / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D013902:Radiography, Thoracic; D013147:Spirometry; D014057:Tomography, X-Ray Computed
chemical_list: D018927:Anti-Asthmatic Agents