Inspiratory and Expiratory Computed Tomography Imaging Clusters Reflect Functional Characteristics in Chronic Obstructive Pulmonary Disease

• Published in: International journal of chronic obstructive pulmonary disease 2023-01, Vol.18, p.1047-1055
• Main Authors: Matsuo, Yumiko, Ogawa, Emiko, Tsunoda, Yoko, Yamazaki, Akio, Kawashima, Satoru, Uchida, Yasuki, Nakagawa, Hiroaki, Kinose, Daisuke, Yamaguchi, Masafumi, Nakano, Yasutaka
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Cluster Analysis; computed tomography; copd; CT imaging; Diagnostic imaging; dpm; emphysema; Exhalation; Female; gas-trapping; Humans; Inhalation; Lung diseases, Obstructive; Male; Middle Aged; Original Research; Pulmonary Disease, Chronic Obstructive - diagnostic imaging; Pulmonary Disease, Chronic Obstructive - physiopathology; Tomography, X-Ray Computed - methods
• ISSN: 1178-2005; 1176-9106; 1178-2005
• DOI: 10.2147/COPD.S405845

Disease probability measure (DPM) is a useful voxel-wise imaging assessment of gas-trapping and emphysematous lesions in patients with chronic obstructive pulmonary disease (COPD). To elucidate the progression of COPD, we performed a cluster analysis using the following DPM parameters: normal (DPM ), gas-trapping (DPM ), and emphysematous lesions (DPM ). Our findings revealed the characteristics of each cluster and the 3-year disease progression using imaging parameters. Inspiratory and expiratory chest computed tomography (CT) images of 131 patients with COPD were examined, of which 84 were followed up for 3 years. The percentage of low attenuation volume (LAV%) and the square root of the wall area of a hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10) were quantitatively measured using inspiratory chest CT. A hierarchical cluster analysis was performed using the DPM parameters at baseline. Five clusters were named according to the dominant DPM parameters: normal (NL), normal-GasTrap (NL-GT), GasTrap (GT), GasTrap-Emphysema (GT-EM), and Emphysema (EM). Women were predominantly diagnosed with GT. Forced expiratory volume in 1 s gradually decreased in the following order: NL, NL-GT, GT, GT-EM, and EM. DPM correlated well with LAV%. Four clusters other than NL showed significantly higher values of √Aaw at Pi10 than NL; however, no significant differences were observed among them. In all clusters, DPM increased after 3 years. DPM only increased in the GT cluster. Clusters using DPM parameters may reflect the characteristics of COPD and help understand the pathophysiology of the disease.