title: Quantitative assessment of bronchial wall attenuation with thin-section CT: An indicator of airflow limitation in chronic obstructive pulmonary disease.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the relation between bronchial wall attenuation on thin-section CT images and airflow limitation in persons with chronic obstructive pulmonary disease.
  
  
  METHODS
  One hundred fourteen subjects (65 men, 49 women; age range, 56-74 years) enrolled in the National Lung Screening Trial underwent chest CT and prebronchodilation spirometry at a single institution. At CT, mean peak wall attenuation, wall area percentage, and luminal area were measured in the third, fourth, and fifth generations of the right B(1) and B(10) segmental bronchi. Correlations with forced expiratory volume in the first second of expiration (FEV(1)) expressed as percentage of predicted value were evaluated with Spearman's rank correlation test.
  
  
  RESULTS
  The peak wall attenuation of each generation of segmental bronchi correlated significantly with FEV(1) as percentage of predicted value (B(1) third, r = -0.323, p = 0.0005; B(1) fourth, r = -0.406, p < 0.0001; B(1) fifth, r = -0.478, p < 0.0001; B(10) third, r = -0.268, p = 0.004; B(10) fourth, r = -0.476, p < 0.0001; B(10) fifth, r = -0.548, p < 0.0001). The correlation coefficients were higher in peripheral airway generations. Wall area percentage and luminal area had similar significant correlations. In multivariate analysis to predict FEV(1) as percentage of predicted value, the coefficient of determination of the model with the combination of percentage of low-attenuation area (< -950 HU) and peak wall attenuation of the fifth generation of the right B(10) was 0.484; the coefficient of determination with percentage of low-attenuation area and wall area percentage was 0.40.
  
  
  CONCLUSIONS
  Peak attenuation of the bronchial wall measured at CT correlates significantly with expiratory airflow obstruction in subjects with chronic obstructive pulmonary disease, particularly in the distal airways.
authors.affiliation: Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Yamashiro
authors.forename: Shin
authors.initials: S
authors.lastname: Matsuoka
authors.forename: Raúl San José
authors.initials: RS
authors.lastname: Estépar
authors.forename: Mark T
authors.initials: MT
authors.lastname: Dransfield
authors.forename: Alejandro
authors.initials: A
authors.lastname: Diaz
authors.forename: John J
authors.initials: JJ
authors.lastname: Reilly
authors.forename: Samuel
authors.initials: S
authors.lastname: Patz
authors.forename: Sadayuki
authors.initials: S
authors.lastname: Murayama
authors.forename: Edwin K
authors.initials: EK
authors.lastname: Silverman
authors.forename: Hiroto
authors.initials: H
authors.lastname: Hatabu
authors.forename: George R
authors.initials: GR
authors.lastname: Washko
mesh_terms: D000368:Aged; D000465:Algorithms; D001995:Bronchography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*