title: Chronic obstructive pulmonary disease: lobe-based visual assessment of volumetric CT by Using standard images--comparison with quantitative CT and pulmonary function test in the COPDGene study.
abstract: OBJECTIVE
  To provide a new detailed visual assessment scheme of computed tomography (CT) for chronic obstructive pulmonary disease (COPD) by using standard reference images and to compare this visual assessment method with quantitative CT and several physiologic parameters.
  
  
  METHODS
  This research was approved by the institutional review board of each institution. CT images of 200 participants in the COPDGene study were evaluated. Four thoracic radiologists performed independent, lobar analysis of volumetric CT images for type (centrilobular, panlobular, and mixed) and extent (on a six-point scale) of emphysema, the presence of bronchiectasis, airway wall thickening, and tracheal abnormalities. Standard images for each finding, generated by two radiologists, were used for reference. The extent of emphysema, airway wall thickening, and luminal area were quantified at the lobar level by using commercial software. Spearman rank test and simple and multiple regression analyses were performed to compare the results of visual assessment with physiologic and quantitative parameters.
  
  
  RESULTS
  The type of emphysema, determined by four readers, showed good agreement (κ = 0.63). The extent of the emphysema in each lobe showed good agreement (mean weighted κ = 0.70) and correlated with findings at quantitative CT (r = 0.75), forced expiratory volume in 1 second (FEV(1)) (r = -0.68), FEV(1)/forced vital capacity (FVC) ratio (r = -0.74) (P < .001). Agreement for airway wall thickening was fair (mean κ = 0.41), and the number of lobes with thickened bronchial walls correlated with FEV(1) (r = -0.60) and FEV(1)/FVC ratio (r = -0.60) (P < .001).
  
  
  CONCLUSIONS
  Visual assessment of emphysema and airways disease in individuals with COPD can provide reproducible, physiologically substantial information that may complement that provided by quantitative CT assessment.
authors.affiliation: Department of Radiology, Division of Biostatistics and Bioinformatics, and Department of Internal Medicine, National Jewish Health, University of Colorado Denver School of Medicine, Denver, Colorado, USA.
authors.forename: Song Soo
authors.initials: SS
authors.lastname: Kim
authors.forename: Joon Beom
authors.initials: JB
authors.lastname: Seo
authors.forename: Ho Yun
authors.initials: HY
authors.lastname: Lee
authors.forename: Dipti V
authors.initials: DV
authors.lastname: Nevrekar
authors.forename: Anna V
authors.initials: AV
authors.lastname: Forssen
authors.forename: James D
authors.initials: JD
authors.lastname: Crapo
authors.forename: Joyce D
authors.initials: JD
authors.lastname: Schroeder
authors.forename: David A
authors.initials: DA
authors.lastname: Lynch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D012044:Regression Analysis; D012129:Respiratory Function Tests; D012907:Smoking / Q000453:epidemiology; D014057:Tomography, X-Ray Computed / Q000379:methods*