Spectral CT Evaluation Of Pulmonary Blood Flow And Its Application In The Chronic Obstructive Pulmonary Disease

Objective:1.Analysis of the pulmonary blood flow in normal people by the use of CT imaging,and the feasibility of the CT imaging method for pulmonary blood flow.2.Analysis of pulmonary perfusion parameters in different regions of healthy people,and preliminarily understand the distribution characteristics of pulmonary blood flow in physiological state.3.To understand the differences between normal and chronic obstructive pulmonary disease?COPD?patients in different areas of lung perfusion parameters,and to explore the evaluation and diagnostic significance of energy spectral CT in COPD.4.To explore the difference in the patients with COPD pulmonary blood flow between different levels and energy spectral CT diagnostic value of different levels in patients with COPD.Methods:The GSI mode scanning was enhanced by using the energy spectral CT.First,the lung tissue was divided into three coronal planes,such as ventral,tracheal plane and dorsal side,in the position of supine position.The two lungs are divided into upper,middle and lower parts from top to bottom.The left and right lung are divided into three levels:outer,middle and inner.The standard iodine concentration values and 70keV image lung CT values were measured evenly in each area at the single level of the arterial phase.SPSS18.0 software was used for statistical analysis using variance analysis,Bonferroni method and paired t test.Results:1.There were significant differences in the total lung standard iodine concentration in COPD and healthy people,but there was no significant difference in lung CT value in 70keV images.2.There was no significant difference in the comparison between the three levels of standard iodine concentration in the COPD group and the healthy people group in the ventral,tracheal plane,dorsal side,upper,middle and lower part,and in the external,middle and inner belt.3.The standard iodine concentration of lung external belt was positively correlated with FEV₁,FEV₁%and FEV₁/FVC.Lung periphery CT value had no obvious correlation with lung function parameters.The middle of lung and dorsal lung CT value had a positive correlation with FEV₁/FVC and FEV₁%expected.4.Standard iodine density and CT value in the lungs,the lungs with standard density and CT value of iodine,iodine on lung standard density and CT value,in standard iodine density and lung CT value,the standard iodine density and lung CT value,ventral standard density and CT value of iodine,trachea plane standard density and CT value of iodine,dorsal standard iodine level was associated with lung function parameters and CT value FEV₁ and FVC,FEV₁/FVC,FEV₁%expected value had no obvious relevance.5.There was a significant difference in the standard iodine concentration of the lung in patients with moderate and severe COPD,and there was no significant difference in CT value.There was no significant difference in the standard iodine concentration and CT value in other regions of COPD patients at different levels,and there was no significant difference between the standard iodine concentration and CT value in other areas of patients with mild to moderate and severe COPD.6.There was a significant correlation between the lung periphery standard iodine concentration and smoking index in patients with COPD,and there was no correlation between lung CT value and smoking index.The standard iodine concentration and CT value in all regions were not significantly correlated with body mass index,age,gender and address.Conclusion:1.Spectral CT perfusion imaging showed that in healthy people physiological state,the pulmonary blood flow was gradient distributed in the direction of gravity,and the dorsal blood flow was more abundant.On the cross section,the closer the lung tissue is to the larger vessels,the more abundant the blood flow.2.It is feasible to evaluate the condition of pulmonary blood flow by spectral CT.3.Spectral CT has the potential to be an indicator of the comprehensiveevaluation of patients with COPD.4.Between moderate and severe COPD patients exist difference in the lung periphery blood flow.