Abstract
Background: Airway abnormalities are a key feature of COPD, although these are poorly characterised. In this study we used CT coupled with image analysis software to perform a detailed analysis of the large/intermediate airways in COPD.
Methods: Subjects with mild-moderate COPD and controls each had an inspiratory chest CT. CT analysis was performed by VIDA Diagnostics using Apollo software. The airway tree was automatically segmented and labelled from the trachea to the sub-segmental bronchi. The total airway count (TAC) was measured by summing all airway segments from the segmented airway tree. In addition, cross-sectional airway area, airway wall area, lumen area and wall area % were measured in each of the third to eight generation airways.
Results: 38 COPD subjects, 18 never and 23 ex-smokers were recruited. TAC was significantly reduced in COPD (218, IQR 131) compared to never (391, IQR 191) and healthy ex-smokers (374, IQR 203) (p<0.001). This reduction in airways in COPD subjects was seen throughout each of the five lobes and started relatively proximally in generation 5 airways.
Airway area was significantly lower in COPD compared to controls in generations 5-8 (p<0.05). Wall area was reduced in COPD subjects in generations 5 and 7 (p<0.05). Lumen area was reduced in generations 4-8 in COPD subjects (p<0.05). Wall area % was significantly higher in all generations (p<0.05) apart from generation 7. No differences were seen in airway dimensions between ex and never smokers.
Conclusion: Using CT image analysis, fewer and smaller airways were seen in COPD subjects compared to controls. The reasons for this is unclear, but may indicate an abnormal remodelling process occurring within the larger airways.
Footnotes
Cite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA4811.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2019