Value Of Dual-source Photons CT With Dual-energy Scan In Differentiating Pulmonary Benign Tumors From Malignancy

Part one Value of iodine image with Dual-energy scan in differentiating pulmonary benign tumors from malignancyObjective:To explore the value of iodine image with Dual-energy scan in differentiating pulmonary benign tumors from malignancy.Methods:Dual-energy CT images of 41 cases with pulmonary tumors(11 benign cases,30 malignant cases)confirmed by pathology were analyzed retrospectively from September 2015 to March 2016.All patients underwent dual-energy plain scan and double-phase enhanced scans with Dual-source Photons CT.Select the "Lung Nodules" mode to obtain the iodine image.The increased CT values of arterial phase(CTAP)and venous phase(CTVP),the difference of CT values between arterial and venous phase(CTAV),CT values on iodine images in arterial-(CTIAP)and venous-phase(CTIVP)and the difference of CT values between arterial-and venous-phase iodine images(CTIAV)were measured.The independent sample t test was performed to compare the differences between pulmonary benign and malignant tumors.Receiver operating characteristic(ROC)curves were generated to assess the diagnostic value.Result:There were no statistically differences of CTAP,CTVP,CTIAP and CTIVP between benign and malignant tumors(P>0.05).However statistically significant differences of CTAV and CTIAV were seen between benign and malignant tumors(t=2.70,P<0.05;t=3.38,P<0.05).Sensitivity?specificity and the area under curve for differentiating pulmonary benign and malignant tumors by CTAV were 63.6%,83.3%,0.724 respectively;by CTIAV were 72.7%,90.0%,0.811?Conclusion:With Dual-energy CT quantitative analysis of iodine maps,It can sensitively reflect the pathological changes of blood flow.Iodine images may be a feasible tool for the measurement of the degree of enhancement?Relative to the change of the conventional CT enhanced value,iodine maps can improve the sensitivity and specificity for diagnosis,and provides a new diagnostic method to differentiate pulmonary benign tumors from malignancy.Part two Value of spectral imaging technique with Dual-energy scan in differentiating pulmonary benign tumors from malignancyObjective:To explore the value of spectral imaging technique with Dual-energy scan in differentiating pulmonary benign tumors from malignancy.Methods:Dual-energy CT images of 41 cases with pulmonary tumors(11 benign cases,30 malignant cases)confirmed by pathology were analyzed retrospectively from September 2015 to March 2016.All patients underwent dual-energy plain scan and double-phase enhanced scans with Dual-source Photons CT.Select the“Monoenergetic”program to obtain the Monochromatic image and spectrum curve.Monochromatic CT value of 40-190 ke V in the arterial and venous phase were measured.Then compared the differences between pulmonary benign and malignant tumors,and analyzed the spectrum curve characteristics of benign and malignant tumors in arterial and venous phase.The repetitive measurement deviation analysis was performed to compare the differences of spectrum curve between pulmonary benign and malignant tumors.Result:From 40 to 190 ke V,spectrum curves of benign and malignant tumors both in arterial and venous phase showed descending tendency.During the 40-80 ke V level in arterial phase,spectrum curve of malignant tumors located above that of benign tumors,and was relatively steep;The curve on 80 ke V level had overlap;During the 80-190 ke V level,spectrum curve of benign tumors lccated above that of malignant tumors,and tended to straight;But the difference of spectrum curve in arterial phase between benign and malignant tumors was no statistically significant(F=0.004,P>0.005).During the 40-190 ke V in venous phase,spectrum curve of benign tumors always lccated above that of malignant tumors,The difference of spectrum curve between benign and malignant tumors was statistically significant(F=5.144,P<0.005).Conclusion:Spectral curve can reflect different material structure and different histopathologic types.It provides more information for the diagnosis and differential diagnosis of benign and malignant lung lesions,and expands the application of dual energy spectrum imaging in lung disease diagnosis.