title: Longitudinal shape irregularity of airway lumen assessed by CT in patients with bronchial asthma and COPD.
abstract: BACKGROUND
  Airway remodelling in bronchial asthma (BA) and COPD has been quantitatively assessed by analysing the airway wall area and the luminal area on cross-sectional CT images. To date, there have been no reports on assessment of the longitudinal structure of the airway lumen.
  
  
  METHODS
  Quantitative airway analysis using CT was performed on three groups consisting of 29 patients with BA, 58 patients with COPD and 59 healthy controls. To assess the longitudinal shape irregularity of the airway lumen, new quantitative CT parameters, validated by a phantom study, were established. The internal radii of imaginary inscribed spheres in the airway lumen were measured as a function of distance from the level of the carina to the fifth-order branches of the right posterior basal bronchus. The gaps of these radii from the regression line were calculated as parameters to reflect the longitudinal airway lumen shape irregularity. These new parameters were compared among the study groups as well as with the conventional parameters of airway wall thickening and luminal area.
  
  
  RESULTS
  Longitudinal airway lumen shape irregularity was significantly greater in patients with COPD than in those with BA and healthy controls. Wall thickening was significantly greater, and luminal area smaller, in patients with BA than in those with COPD and healthy controls. These results were consistent even among the BA and COPD subgroups with similar airflow limitation.
  
  
  CONCLUSIONS
  The combination of cross-sectional and longitudinal airway structure analyses using CT images may suggest differences in the characteristics of airway remodelling between COPD and asthma.
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Oguma
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Toyohiro
authors.initials: T
authors.lastname: Hirai
authors.affiliation: Respiratory Disease Center, Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan.
authors.forename: Motonari
authors.initials: M
authors.lastname: Fukui
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Tanabe
authors.affiliation: Respiratory Disease Center, Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Marumo
authors.affiliation: Department of Preventive Medicine, Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Department of Radiology, Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Ito
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Sato
authors.affiliation: Department of Medical Oncology and Immunology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Niimi
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Ito
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Hisako
authors.initials: H
authors.lastname: Matsumoto
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Muro
authors.affiliation: Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Michiaki
authors.initials: M
authors.lastname: Mishima
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D056151:Airway Remodeling / Q000502:physiology*; D001249:Asthma / Q000000981:diagnostic imaging* / Q000503:physiopathology; D001980:Bronchi / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000503:physiopathology
keywords: Asthma; Imaging/CT MRI etc