The Different Value Of Lung Nodules Or Mass Using Dual-energy Spectral CT Imaging

Objective: To evaluate the clinical utility of dual energy spectral CT imaging indifferentiating Pulmonary Carcinoma from tuberculosis nodule.Methods and Materials: From Apr.2011to Dec.2011in our hospital,44cases ofpatients with pulmonary nodules underwent dual-energy pulmonarycontrast-enhanced dual-phase CT scan (GE Discovery CT750HD with single source,dual energy and fast80/140kVp switching) and were analyzed retrospectively. Alldata were transmitted to AW4.5to obtain monochromatic images and materialdecomposition images in arterial phase (AP) and balance period (BP). Iodine densityon material decomposition images, and the mean slope rate of HU curve((HU40kev-HU100kev）/（-60）)were respectively measured both in AP and BP. Allthe results were correlated with pathological findings and were analyzed by pairedsamples T test.Results: There were26Pulmonary adenocarcinoma,11Pulmonary squamous cellcarcinoma and7pulmonary tuberculosis with9nodules confirmed pathologically.The iodine density of pulmonary carcinoma and tuberculosis were respectively（1.30±0.51）mg/cc vs.（0.84±0.53）mg/cc(AP)，and（1.50±0.44）mg/cc vs.（0.81±0.47）mg/cc(BP). The mean slope rate of HU curve of pulmonary carcinoma andtuberculosis were respectively（-1.55±0.67）vs（.-1.01±0.61）(AP)，（-1.78±0.53）vs.（-0.96±0.55）(BP).There were statistically difference of Iodine density(P<0.05)and the mean slope rate of HU curve (P<0.05) between pulmonary carcinoma andtuberculosis both in AP and BP. But there were no significant difference betweenpulmonary adenocarcinoma and pulmonary squamous cell carcinoma. Conclusions: Iodine density and the slope rate of HU curve could be used todifferentiate pulmonary carcinoma and tuberculosis in contrast-enhanced CT scan.But at present it was still hard to differentiate pulmonary adenocarcinoma frompulmonary squamous cell carcinoma in spectral contrast-enhanced CT scan. Thediagnosis and differentiated diagnosis of pulmonary nodules are very important inclinic. Gemstone Spectral CT Imaging affords a promising method to differentiatepulmonary carcinoma and tuberculosis nodule.