title: Automated CT scan scores of bronchiectasis and air trapping in cystic fibrosis.
abstract: BACKGROUND
  Computer analysis of high-resolution CT (HRCT) scans may improve the assessment of structural lung injury in children with cystic fibrosis (CF). The goal of this cross-sectional pilot study was to validate automated, observer-independent image analysis software to establish objective, simple criteria for bronchiectasis and air trapping.
  
  
  METHODS
  HRCT scans of the chest were performed in 35 children with CF and compared with scans from 12 disease control subjects. Automated image analysis software was developed to count visible airways on inspiratory images and to measure a low attenuation density (LAD) index on expiratory images. Among the children with CF, relationships among automated measures, Brody HRCT scanning scores, lung function, and sputum markers of inflammation were assessed.
  
  
  RESULTS
  The number of total, central, and peripheral airways on inspiratory images and LAD (%) on expiratory images were significantly higher in children with CF compared with control subjects. Among subjects with CF, peripheral airway counts correlated strongly with Brody bronchiectasis scores by two raters (r=0.86, P<.0001; r=0.91, P<.0001), correlated negatively with lung function, and were positively associated with sputum free neutrophil elastase activity. LAD (%) correlated with Brody air trapping scores (r=0.83, P<.0001; r=0.69, P<.0001) but did not correlate with lung function or sputum inflammatory markers.
  
  
  CONCLUSIONS
  Quantitative airway counts and LAD (%) on HRCT scans appear to be useful surrogates for bronchiectasis and air trapping in children with CF. Our automated methodology provides objective quantitative measures of bronchiectasis and air trapping that may serve as end points in CF clinical trials.
authors.affiliation: Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO. Electronic address: emily.deboer@childrenscolorado.org.
authors.forename: Emily M
authors.initials: EM
authors.lastname: DeBoer
authors.affiliation: Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Swiercz
authors.affiliation: Department of Pediatrics, Seattle Children's and University of Washington School of Medicine, Seattle, WA.
authors.forename: Sonya L
authors.initials: SL
authors.lastname: Heltshe
authors.affiliation: Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO.
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Anthony
authors.affiliation: Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO.
authors.forename: Paul
authors.initials: P
authors.lastname: Szefler
authors.affiliation: Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Klein
authors.affiliation: Department of Radiology, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO.
authors.forename: John
authors.initials: J
authors.lastname: Strain
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
authors.forename: Alan S
authors.initials: AS
authors.lastname: Brody
authors.affiliation: Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO.
authors.forename: Scott D
authors.initials: SD
authors.lastname: Sagel
mesh_terms: D001331:Automation / Q000379:methods*; D001987:Bronchiectasis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D003550:Cystic Fibrosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000401:mortality; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014481:United States / Q000453:epidemiology; D014797:Vital Capacity