Predictive Value Of Quantitative Parameters Of Chronic Obstructive Pulmonary Disease Based On MSCT For Pulmonary Function Indexes

Objective Through MSCT,quantitative analysis of lung parenchyma and airway parameters in patients with chronic obstructive pulmonary disease was performed to evaluate the correlation between quantitative CT lung function parameters and conventional lung function indicators,and to explore the feasibility analysis of predicting lung function related indicators.Methods A total of 73 patients with COPD and 17 patients in the control group were enrolled,and all subjects underwent chest CT scans and routine pulmonary functional tests.According to the global initiative for chronic obstructive lung disease,patients in the COPD group were divided into 4 groups,and the mild group（GOLD I,II grade）and the severe group（GOLD III,IV grade）were set.The post-processing software of CT was used for quantitative analysis of all subjects.Two independent sample t-tests were used to analyze the differences in general data and lung function indexes between the COPD group and the control group;One-Way ANOVA was used to compare the differences in general data and CT quantitative parameters between the control group and different GOLD grade COPD groups;Pearson correlation analysis was used to quantify the correlation between CT parameters and lung function indicators;Multiple linear regression analysis was used to determine the predictors of conventional lung function indicators.Results（1）The differences in gender,smoking status,and lung function indexes between the COPD group and the control group were statistically significant（P<0.05）,while the differences in age,height,body mass and body mass index were not statistically significant（P>0.05）.（2）There were statistically significant differences in BMI,smoking status and lung function between the COPD group of different GOLD grades and the control group（P<0.05）.（3）There was a statistically significant difference in LAA%,WT,and WA%between the COPD groups and the control group（P<0.05）.Among them,LAA%increased with the increase of GOLD grade;GOLD III,IV WT and WA%were higher than GOLD grade I and II（P<0.05）;however,there was no statistically significant difference in LD between the groups（P>0.05）.（4）Pearson correlation analysis showed that the LAA%of GOLD III grade was moderately negatively correlated with FEV₁,FEV₁/FVC and FEV₁%;for the LAA%of GOLD I,II grade and FEV₁/FVC,there were significant and moderately negative correlations;the LAA%of GOLD I grade was significantly negatively correlated with FEV₁%;the WA%of GOLDII grade was moderately positively correlated with FEV₁/FVC,and BMI was significantly positively correlated with FEV₁%.（5）For all COPD patients,pulmonary parenchymal parameters and airway parameters were predictive of FEV₁%（R²=0.707,P<0.001）,and only pulmonary parenchymal parameters were predictive of FEV₁/FVC（R²=0.578,P<0.001）.For the mild COPD group,lung parenchymal parameters and airway parameters were used as predictors of FEV₁%（R²=0.300,P<0.05）and FEV₁/FVC（R²=0.381,P<0.05）.While in the severe COPD group,only lung parenchymal parameters were used as predictors of FEV₁%（R²=0.610,P<0.001）and FEV₁/FVC（R²=0.410,P<0.001）.Conclusion Quantitative CT parameters have a certain value in predicting pulmonary function indicators.For patients with mild COPD,lung parenchymal parameters（LAA%）and airway parameters（WA%）are the predictors of FEV₁/FVC and FEV₁%,while for patients with severe COPD,only pulmonary parenchymal parameters（LAA%）can be used as the predictor of pulmonary function indicators.