目的：探讨慢性阻塞性肺疾病（Chronic obstructive pulmonary disease，COPD）患者呼、吸双相CT气道定量参数差异及各参数与肺功能（PFT）的相关性。方法：回顾性分析47例经肺功能确诊为COPD的患者，行呼、吸双相CT扫描，将数据导入“Dexin-FACT”自动分析软件，定量分析右肺下叶气道参数，分别为支气管平均壁厚度（Mean wall thickness，MWT）、支气管平均内直径（Mean lumen diameter，MLD）、支气管平均壁面积（Mean wall area，MWA）、管壁面积占支气管断面总面积的百分比的平均值（Mean wall ratio，WA%）。呼、吸双相CT参数差异用配对样本t检验；MWT、MLD、MWA、WA%与肺功能的相关性采用Preason相关性分析法。结果：右肺下叶1～9代支气管双相MWT、MLD和MWA差异均有统计学意义（P＜0.05）；0～3代支气管呼、吸双相WA%差异均有统计学意义（P＜0.05），吸气相WA%大于呼气相，4～9代支气管双相WA%差异无统计学意义（P＞0.05）。右肺下叶9代支气管呼、吸双相MWT、MLD、MWA、WA%与FEV1%、FEV1/FVC、MEF25%均有相关性（P＜0.05）；8代支气管呼气相MWT与FEV1%，双相MWT与MEF25%，双相MLD与MEF25%，双相WA与FEV1%、MEF25%，呼气相WA与FEV1/FVC，双相WA%与FEV1%、FEV1/FVC、MEF25%均有相关性（P＜0.05）；7代支气管双相WA%与FEV1%、FEV1/FVC、MEF25%均有相关性（P＜0.05）。各支气管定量参数与PFT均成负相关，相关性随代数的增加逐渐升高，呼气相与PFT的相关性较吸气相更高，其中9代支气管呼气相WA%与MEF25%相关性最高（|r|=0.697，P＜0.05）。余各代支气管与PFT均无相关性（P＞0.05）。结论：基于呼、吸双相CT扫描对COPD患者小气道疾病的诊断具有重要意义，可更好地指导临床个体化治疗。

Objective: To investigate the differences in airway quantitative parameters of respiratory biphasic CT and the correlation between various parameters and pulmonary function in patients with chronic obstructive pulmonary disease(COPD). Methods: We retrospectively analyzed 47 patients with pulmonary function diagnosed as COPD who underwent expiratory and inspiratory biphasic CT scan. Then we imported the data into the “Dexin-FACT” automatic analysis software, quantitatively analyzed the airway parameters in right lower lobe, including the mean wall thickness(MWT) of the bronchus, the average diameter(MLD) of the bronchial lumen, the mean wall area(MWA) of the bronchial wall area and the percentage of the wall area(mean wall ratio, WA%). Paired sample t test was used to determine the differences of CT parameters; correlation between MWT, MLD, MWA, WA% and lung function was performed by using Preason correlation analysis. Results: There were significant differences in bronchial MWT, MLD, MWA and WA% between the two groups of respiratory and inspiratory phases(P<0.05). MWT of inspiratory was bigger than expiratory; MLD and MWA of expiratory are bigger than inspiratory phase; there were statistically significant differences in WA% between biphasic CT in 0～3th generations of bronchi(P<0.05). WA% of inspiratory was bigger than expiratory, there were no statistically significant differences among WA% of 4th～9th generations bronchi(P>0.05). The MWT, MLD, MWA, WA% and FEV1%, FEV1/FVC, MEF25% of 9th generation bronchi in biphasic CT have correlations in the right lower lobe(P<0.05); In 8th generation of bronchi, MWT and FEV1% at expiratory, MWT and MEF25% in biphasic CT, MLD and MEF25% in biphasic CT, WA and FEV1%, MEF25% in biphasic CT, WA and FEV1/FVC at expiratory, WA% and FEV1%, FEV1/FVC, MEF25% in biphasic CT were have some correlations(P<0.05); There were some correlations between WA% and FEV1%, FEV1/FVC, MEF25% of 7th generation of bronchi in biphasic CT(P<0.05). The quantitative parameters of each bronchus have negative correlations with PFT, and the correlations increased with the increase of generations. The correlations between parameters at expiratory and PFT was higher than that of inspiratory. The WA% of bronchi of 9th generation in expiratory have the highest correlation with MEF25%(|r|=0.697, P<0.05). There were no correlations between other bronchi and PFT(P>0.05). Conclusion: Biphasic CT scanning is important for the diagnosis of small airway diseases in patients with COPD, so as to better guide clinical individualized treatment.