| Objective:To explore the diagnostic value of first-pass dual-input perfusion on 320-slice CT and TDC maximum-slope method on identifying benign and malignant solitary pulmonary nodules.Analyze the perfusion parameters of BF,PF,PI,TPF and in TDC curve the maximum slope of before and after left atrium tmax appearance for differentiating benign and malignant solitary pulmonary nodules.Provide the basics of early diagnosis,treatment,and assessment of SPNs.Methods:Analyze 51 patients with solitary pulmonary nodules detected on CT scans in the hospital,all the patients underwent double-input lung perfusion on 320-slice CT scan and have pathologically proven 35 of them had malignant nodules and 16 had benign ones.All the scans performed by Aquilion One 320-row CT Lung Perfusion scan program on volume scanning.Double-input perfusion software is used for data collection,processing,and analyzing the pulmonary flow(PF),bronchial flow(BF),and perfusion index[PI=PF/(PF+BF)],figure out the total perfusion(TPF),the changes of slopes of ascending time-density curve(TDC)and the left atrial-time to peak(LA-TTP)of benign and malignant nodules.All data were used with the SPSS statistical software,P<0.05 showed as there is a statistically significant difference between two groups.Results:1.Perfusion parameter:There was a statistically significant difference between bronchial arterial blood flow(BF)of malignant and benign SPNs(P<0.01).There was a statistically significant difference between perfusion index(PI)in two groups(P<0.01).The benign SPN group divided into inflammatory SPN and tuberculoma SPN group,compared perfusion parameters of malignant,inflammatory and tuberculoma SPNs group.The BF value of malignant SPNs group compared with inflammatory groupand tuberculoma group respectively,there were statistical differences(P<0.01,P<0.01)on both coparisons;the PF value of inflammatory SPN group compared with malignant group and tuberculoma group respectively,there were statistical differences(P<0.01,P<0.01)on both coparisons;the PI value of malignant,inflammatory and tuberculoma compared to each other,there were statistical differences(Malignant group,inflammatory group compared with P<0.01,Malignant group,tuberculoma group compared with P<0.05,inflammatory group,tuberculoma group compared with P<0.01);the TPF value of tuberculoma SPNs group compared with malignant and inflammatory group respectively,there were statistical differences(P<0.01,P<0.05)on both coparisons.2.Peak time comparison:There is no statistical difference on pulmonary artery time to peak(PA-TTP),left atrium time to peak(LA-TTP),aorta time to peak(A-TTP)and SPN time to peak(SPN-TTP)of two groups(P>0.05).3.Maximum slope comparison:There was a statistical difference between the maximum slope of rising curve before left atrium time to peak of TDC in two groups;the maximum slope of rising c.urve after left atrium time to peak in two groups;the overall slope of TDC curve of two groups(P<0.05,P<0.05,P<0.01).There was a statistical difference the maximum slope of rising curve before and after left atrium time to peak of TDC in two groups(P<0.01),called aortic curve,a total of 35 cases of malignant TDC curve were such curves;there was a statistical difference the maximum slope of rising curve before and after left atrium time to peak of TDC in two groups in the malignant group,(P<0.01),called pulmonary arterial curve,11 cases of inflammatory SPN curve showed a typical pulmonary artery curve,5 cases of tuberculosis ball SPN curve showed a slow decline in the low curve,known as the tuberculosis ball curve.4.After ROC curve analysis,the area of ROC of PI value is maximum,the maximum area is 0.952(P<0.01).The area of ROC of BF,PF and TPF are respectively 0.084,0.570 and 0.332.When the value of PI<47.85%,the sensitivity and specificity of the diagnosis of malignant SPNs are the highest,87.50%,91.40%respectively.5.By Spearman correlation analysis,the correlation between the diameters of the malignant group and the value of PI is the strongest,the correlation coefficient is-0.701(P<0.01),the correlation coefficient of BF,PF,and TPF are not large.6.The comparison of malignant perfusion indexes of each pathological classification:There is no statistical difference between perfusion parameters of adenocarcinoma,squamous carcinoma and small cell lung cancer(P>0.05).Conclusion:The perfusion parameters using first-pass dual-input perfusion on 320-slice CT and the application of TDC maximum-slope method can provide strong references for the blood supply of SPNs and the diagnosis of benign and malignant SPNs. |
