HRCT肺小血管面积定量测量与COPD小气道功能的相关性研究

目的 探讨高分辨率CT (HRCT)肺小血管面积与肺截面积比值(％CSA)与慢性阻塞性肺疾病(COPD)患者肺部小气道功能的相关性.方法 选取我院收治入院的连续性COPD患者105例,同时纳入年龄、性别相匹配健康对照组100例.所有纳入者均接受胸部HRCT扫描及肺功能检查.分析所有纳入者的主要小气道肺功能指标(MMEF...

Quantitative measurement of pulmonary small blood vessel area in COPD using high resolution computed tomography:correlation with small airway function

Objective To explore the correlation between the percentage of cross-sectional area of small pulmonary vessels for the lung area(%CSA)in high-resolution CT and the function of small airways in patients with chronic obstructive pulmonary disease(COPD).Methods A total of 105 consecutive COPD patients admitted to our hospital were enrolled into this study.In the meantime,100 age/gender matched healthy cases were served as the control group.All subjects received HRCT and pulmonary function examination.The main small airway pulmonary function indexes(MMEF%,MEF 50.00%and MEF25.00%)and impulse concussion indexes IOS(Z5,R5,R20,Fres,X5)were analyzed.The main small airway pulmonary function indexes(MMEF%,MEF50.00%and MEF25.00%)and impulse concussion indexes IOS(Z5,R5,R20,Fres,X5)were analyzed.The%CSA parameters based on HRCT were measured by Image J image processing software,including pulmonary microvascular cross-sectional area<5 mm²(%CSA_<5)and 5~10 mm²(%CSA_5-10).The differences of lung function and HRCT parameters between COPD and control group were compared by independent sample t-test;The correlation between%CSA and small airway indicators of COPD group was analyzed by Spearman correlation.Receiver operating characteristic analysis(ROC)was performed to determine whether CSA%parameters could be used in discriminating small airway dysfunction in COPD subjects.Results In COPD group,the small airway lung function indexes(MMEF%,MEF50.00%and MEF25.00%)were significantly lower than those in the control group,which was also gradually decreased accompanied by increase of the severity of COPD.Compared with the control group,the IOS indexes Z5,R5 and Fres were higher while X5 was decreased.The Z5,R5 and Fres were gradually increased with increased of severity of COPD.The%CSA_<5 and%CSA_5-10 in COPD group were significantly lower than those in the control group,and there were also significant differences in the%CSA_<5 among different COPD groups(all P<0.05).In COPD patients,the pulmonary function index(MMEF%,MEF50.00%and MEF25.00%)of small airway was positively correlated with%CSA_<5 and%CSA_5-10,while the IOS index(Z5,R5,Fres)was negatively correlated with%CSA parameters(all P<0.05).The ROC curve analysis revealed that AUC values of%CSA_<5 and%CSA_5-10 were 0.959 and 0.931,respectively.When the threshold value of%CSA_<5 was 0.71%,there was a better sensitivity(89.30%)and specificity(93.80%)in diagnosing small airway dysfunction in COPD patients.Conclusion As quantitative measurement parameters pf pulmonary small vessel area of HRCT,%CSA_<5 and%CSA_5-10 are relative good correlated with the small airway function,and could be used to accurately evaluate the small airway dysfunction in COPD patients,which has more important clinical significance.