Correlation Between CT Bronchi Quantitative Parameters And Lung Function In Patients With COPD

Objective:The lumen area(LA)and the percentage of wall area(WA%)of the 3rd to 6th branch of the upper lobe bronchi,3rd to 8th branch of the lower lobe bronchi between the normal physical examination(normal control group)and all levels of COPD were been compared,and the correlation between LA,WA%and lung function indicators FEV1,FEV1/FVC,FEF25 and MMEF75/25 at all levels of bronchi were analyzed.The CT parameters of the normal control group,mild COPD group CT(-)and moderate COPD group CT(-)were compared,and their correlations with lung function small airway indexes FEF25 and MMEF75/25 were analyzed.To investigate the clinical value of CT bronchial quantitative parameters in evaluating the condition of COPD patients and the feasibility of early diagnosis of COPD.Methods:Collected 120 cases of COPD patients and healthy subjects from November 2018 to December 2019,There were 30 patients in the healthy subjects,the mild,moderate and severe COPD patients respectively.The mild and moderate COPD groups were divided into CT(+)group and CT(-)group according to the presence or absence of emphysema of CT.All people need to undergo strict breathing training,Chest CT scan was performed at the end of a deep inspiration with the uCT 760.Lung function tests were performed within one week,and the ratio of actual and predicted values of FEV1,FEV1/FVC,FEF25,and MMEF75/25 were been recorded.United Imaging Post-processing analysis software was used to process CT images and record the 3-6 LA,WA%of the left upper lung lobe posterior segment and the right upper lobe segment and 3-8 bronchi LA and WA%of the posterior basal segment of both lungs.The differences of each lobe LA,WA%between normal group and COPD mild,moderate and severe groups were been compared,and Pearson correlation analysis was used to compare the correlation between CT parameters and lung function parameters.To compare the differences of CT parameters between the normal group,mild COPD group CT(-),and moderate COPD group CT(-),and correlation analysis was made between the different index and the ratio of the actual value with the predicted value of FEF25,MMEF75/25,which can reflect the small airway lung function parameters.Results:1.There was no significant difference in age,gender,and body mass index between the normal control group,the mild,moderate,and severe COPD groups(P>0.05);There was no significant difference in age,gender,and body mass index between the normal control group,mild COPD group CT(-),and moderate COPD group CT(-)(P>0.05).2.There was no significant difference in LA and WA%between the normal control group and the COPD mild,moderate and severe groups in the upper lung 3-4 grade bronchi,the right lower lung 3-4 grade bronchi,and the left lower lobe 3-5 grade bronchi(P>0.05).LA,WA%of grade 5-6 bronchi in upper lobe of the lung,grade 5-8 branch of the lower lobe of right lung,and grade 6-8 of the lower lobe of left lung were statistically different between the four groups(P<0.05).3.Comparison between the normal control group and the COPD mild,moderate and severe groups:there was no statistically significant difference in left lung upper 5th bronchial LA and right lower lung 5th bronchial WA%between moderate COPD group and severe COPD group(P>0.05).There was no statistically significant difference in left upper lung 6 grade bronchus LA between normal and mild COPD groups(P>0.05),and there was a significant difference between any other two groups(P<0.05).With the severity of the disease,LA gradually decreased,WA%gradually increased.4.The normal control group and the COPD mild,moderate and severe groups of the upper lung bronchi 5-6 branches and lower bronchial 5-8 branches LA,WA%and lung function parameters FEV1,FEV1/FVC,FEF25,MMEF75/25 were correlated,and the correlation gradually increased with the increase of bronchial progression.5.The correlation between LA and PFT is better than that between WA%and PFT.The correlation between the CT parameters of the peripheral bronchus and the PFT index is the strongest,and the correlation coefficient between the left lower lobe 8 grade bronchus and FEF25 is greater than other lung function indexes.The correlation between LA and PFT in the left lower lobe is better than that in other lung lobes.6.There was no difference between the normal control group,the mild COPD group CT(-),and the COPD moderate group CT(-)in double lung lower lobe grade 5 bronchus LA,WA%and left upper lobe grade 5 bronchus WA%(P>0.05),there were statistically significant differences in LA and WA%in the remaining upper lobe 5-6 and lower lobe 5-8 bronchi(P<0.05).7.The both upper lung lobe 5,6 bronchus,right lower lobe 6 bronchus and both lower lung lobe 7,8 bronchus LA,6 bronchial WA%of the upper and lower lobe of the two lungs and WA%of the bronchus 7 and 8 of the lower lobe of the two lungs between normal control group,mild COPD group CT(-),moderate COPD group CT(-)were correlated with FEF25 and MMEF75/25(P<0.05),and the correlation gradually increased with the increase of bronchial progression of each lung lobe.Conclusions:1.There were differences in the quantitative parameters of the CT bronchus including lumen area(LA)and the percentage of wall area(WA%)between the patients with COPD and normal subjects.people.The changes of the quantitative indexes LA and WA%of CT small airways in COPD patients mostly occurred in grade 5-8 bronchus2.The CT bronchial quantitative parameters LA,WA%(grade 5-8)of COPD patients are correlated with clinical lung function indexes,and the closer to the peripheral,the stronger the correlation was.The correlation between LA and lung function parameters is better than WA%,and the correlation between the left lower lobe and lung function parameters is better than other lung lobes3.CT bronchial quantitative parameters lumen area(LA)and the percentage of wall area(WA%)of grade 5-8 bronchus of COPD patients with negative CT morphology(without emphysema)may be abnormal,and LA,WA%(Level 5-8)were correlated well with clinical pulmonary function parameters,indicating that CT bronchial quantitative analysis can make up for the deficiencies of conventional CT morphology,and it has certain value for the diagnosis of some COPD patients with negative CT morphology.