Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease: systematic review and meta-analysis.
OBJECTIVE
To determine the correlation between CT measurements of emphysema or peripheral airways and airflow obstruction in chronic obstructive pulmonary disease (COPD).


METHODS
PubMed, Embase and Web of Knowledge were searched from 1976 to 2011. Two reviewers independently screened 1,763 citations to identify articles that correlated CT measurements to airflow obstruction parameters of the pulmonary function test in COPD patients, rated study quality and extracted information. Three CT measurements were accessed: lung attenuation area percentage < -950 Hounsfield units, mean lung density and airway wall area percentage. Two airflow obstruction parameters were accessed: forced expiratory volume in the first second as percentage from predicted (FEV(1) %pred) and FEV(1) divided by the forced volume vital capacity.


RESULTS
Seventy-nine articles (9,559 participants) were included in the systematic review, demonstrating different methodologies, measurements and CT airflow obstruction correlations. There were 15 high-quality articles (2,095 participants) in the meta-analysis. The absolute pooled correlation coefficients ranged from 0.48 (95 % CI, 0.40 to 0.54) to 0.65 (0.58 to 0.71) for inspiratory CT and 0.64 (0.53 to 0.72) to 0.73 (0.63 to 0.80) for expiratory CT.


CONCLUSIONS
CT measurements of emphysema or peripheral airways are significantly related to airflow obstruction in COPD patients. CT provides a morphological method to investigate airway obstruction in COPD.


CONCLUSIONS
• Computed tomography is widely performed in patients with chronic obstructive pulmonary disease (COPD)                                                                              • CT provides quantitative morphological methods to investigate airflow obstruction in COPD                                                                              • CT measurements correlate significantly with the degree of airflow obstruction in COPD                                                                              • Expiratory CT measurements correlate more strongly with airflow obstruction than inspiratory CT                                                                              • Low-dose CT decreases the radiation dose for diagnosis and quantitative emphysema evaluation.
Center for Medical Imaging-North East Netherlands (CMI-NEN), Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700, RB, Groningen, The Netherlands.
Xueqian
X
Xie
Pim A
PA
de Jong
Matthijs
M
Oudkerk
Ying
Y
Wang
Nick H T
NH
Ten Hacken
Jingtao
J
Miao
Guixiang
G
Zhang
Geertruida H
GH
de Bock
Rozemarijn
R
Vliegenthart
D006801:Humans; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D012123:Pulmonary Ventilation; D014057:Tomography, X-Ray Computed