Application Of Dual Energy CT In Differentiating Benign And Malignant Pleural Effusion

Objective:To study the application of dual energy CT imaging in differential diagnosis of benign and malignant pleural effusion.Methods:Collected by dual energy CT scans of 80 patients with pleural effusion,according to the results of the clinical various examination and follow-up after treatment,comprehensive analysis,to share a group of patients with benign pleural effusion（40 cases）,a group of patients with malignant pleural effusion（40 cases）,and the electron cloud density（Rho）and effective atomic sequence(Z_eff)values of pleural effusion were calculated after post-processing,and measured in 70 k V,Sn150k V,40 Ke V,50Ke V,60 Ke V,70 Ke V,80 Ke V,90 Ke V,100 Ke V,under the110 Ke V CT value and calculate the spectral curve slope,differences between each data comparison between the two groups by using two independent sample t test.The significantly different CT values,energy spectrum curve slope and Z_effvalues at40Ke V were selected to draw ROC curves to determine the critical values and diagnostic efficiency of the differential diagnosis of benign and malignant pleural effusion.Another 6 patients with pleural effusion were scanned by dual-energy CT enhanced scan,including 4 malignant patients and 2 benign patients.Virtual plain scan technology was used to obtain the entry of contrast agent in pleural effusion.Results:The CT values,slope of energy spectrum curve and Z_effvalues at 70k V,40ke V,50ke V and 60ke V were significantly different between the two groups（P<0.001）,and the CT values at Sn150k V,70ke V,80ke V and 90ke V had statistical significance（P<0.05）.There was no significant difference in Rho value and CT value at 100ke V and 110ke V between the two groups（P>0.05）.The sensitivity of differential diagnosis of benign and malignant pleural effusion was 92.5%,82.5%,82.5%,and the specificity was 50.0%,77.5%,67.5%,respectively.Contrast agent was found in 4of the 6 patients with malignant effusion,while no contrast agent was found in 2benign effusions.Conclusion:The multi-parameter quantitative analysis function of dual-energy CT has certain application value for the differential diagnosis of benign and malignant pleural effusion.