University of Groningen Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease

Objectives To determine the correlation between CTmeasurements 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 (FEV1 %pred) and FEV1 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. Electronic supplementary material The online version of this article (doi:10.1007/s00330-012-2480-8) contains supplementary material, which is available to authorized users. X. Xie :M. Oudkerk :R. Vliegenthart (*) 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 e-mail: r.vliegenthart@umcg.nl P. A. de Jong Department of Radiology, University Medical Center Utrecht, University of Utrecht, Heidelberglaan 100, P.O. Box 85.500, 3584 CX Utrecht, The Netherlands Y. Wang Department of Radiology, Tianjin Medical University General Hospital, Anshan Road 154, 300052, Tianjin, China N. H. T. ten Hacken Department of Pulmonary Diseases, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB Groningen, The Netherlands J. Miao :G. Zhang Department of Radiology, Shanghai Jiao Tong University Affiliated First People’s Hospital, Haining Road 100, 200080, Shanghai, China G. H. de Bock Department of Epidemiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB Groningen, The Netherlands Eur Radiol (2012) 22:2085–2093 DOI 10.1007/s00330-012-2480-8 # The Author(s) 2012. This article is published with open access at Springerlink.com Key Points • 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