Greater parallel heterogeneity of airway narrowing and airway closure in asthma measured by high-resolution CT

摘要: Background Heterogeneous airway narrowing and closure are characteristics of asthma. However, they have never been quantified by direct measurements parallel sister airways obtained from image data, the anatomical basis these processes remains unknown. Methods Seven normal nine asthmatic subjects underwent high-resolution CT, before after methacholine challenge. Mean lumen areas entire were measured in 28 24 pairs (a pair arising same bifurcation) respectively (range 1.0–8.7 mm diameter). was defined as median difference percentage between airways. Forced oscillatory respiratory resistance (R rs ) spirometry challenge conducted while supine. Results The asthmatics smaller at baseline, following bronchoconstriction there similar decreases FEV 1 , increases R mean for non-asthmatic groups. Non-asthmatics required higher doses than to achieve changes. heterogeneity (median (IQR) 33% (27–53%) vs 11% (9–18%), p 2 greater versus non-asthmatics. Conclusion We found clear evidence differences behaviour group. Asthmatic narrower baseline responded inhaled more heterogeneous closure.