Quantitative assessment of bronchial wall attenuation with thin-section CT: An indicator of airflow limitation in chronic obstructive pulmonary disease.
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.
Yamashiro
Tsuneo
T
Center for Pulmonary Functional Imaging, Brigham and Women's Hospital, Boston, MA, USA.
Matsuoka
Shin
S
Estépar
Raúl San José
RS
Dransfield
Mark T
MT
Diaz
Alejandro
A
Reilly
John J
JJ
Patz
Samuel
S
Murayama
Sadayuki
S
Silverman
Edwin K
EK
Hatabu
Hiroto
H
Washko
George R
GR
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*