The application of low dose CT scan and quantitative analysis in airway remodeling and air trapping of asthma

Objective: To explore airway remodeling and air trapping in asthmatic patients with low dose CT scanning and quantitative analysis. Methods: 52 stable asthmatic patients in which 29 were severe and 23 were slight, and 20 healthy control cases were underwent low dose dual phase CT scanning. The LA/BSA, WA/BSA, TA/BSA, WA% and Pi10WA were analyzed as airway remodeling indexes. The MLD of expiratory, VI_-850(%) of expiratory, MLD E/I, VI_-850E-I(%) and VI_-850/-950E-I(%) were analyzed as air-trapping indexes. One-Way ANOVA or H Kruskal-Wallis was used to analyze the above indicators. Results: Airway remodeling indexes and LA/BSA were (9.6 ± 2.6), (11.0 ± 3.4) and (12.6 ± 3.0) mm²/m² in severe asthmatics group, non-severe asthmatics group and healthy control group respectively, and there was significant difference between the three groups (F = 5.60, P = 0.006). WA% of each group was (65.1 ± 2.5)%, (63.3 ± 4.4)% and (62.0 ± 3.0)%, and there was significant difference between the three groups (F = 5.53, P = 0.006). The Pi10WA was (18.4 ± 2.6), (17.7 ± 3.1) and (16.4 ± 1.4) mm² respectively with significant difference between the three groups (F = 3.59, P = 0.033). Air-trapping indexes, MLD of expiratory of each group was -(771 ± 59), -(724 ± 43) and -(676 ± 60) HU respectively with significant difference (F = 5.60, P = 0.006). VI_-850(%) of expiratory of each group was 30.79(30.45)%, 13.53(12.09)% and 2.85(6.87)% respectively with significant difference (H = 17.20, P < 0.001). Conclusions: Low dose of CT scan and quantitative analysis can provide an objective and quantitative information for patients with airway disease of asthma, and both WA% and Pi10WA were objective indexes. The severe asthmatic patients were associated with obvious airway remodeling and air trapping compared with non-severe asthmatic patients. (authors)