Value Of Gemstone Dual Spectral CT Imaging In Differential Diagnosis Of Esophageal Cancer And Metastatic Lymphadenopathy

Objective:To access the value of spectral CT imaging in differential diagnosis of esophageal cancer and metastatic lymphadenopathy.Methods:50 patients with esophageal cancer were retrospectively reviewed.All the patients received contrast enhanced GSCT.The data will be divided into metastatic lymph nodes?group A?and non-metastatic lymph nodes group?group B?and esophageal cancer group?group C?by the postoperative pathological evaluation.The group A and group B and group C both in arterial and venous period,the iodine concentration?IC?,water concentration?WC?,Effective atomic number?Eff-Z?,The spectral curve slope?K?,were made by using the energy spectrum with a dedicated software?GSI Viewer,Advantage Workstation 4.6?.CT values of group A and group B from 40 and140keV were measured form the monochromatic spectral CT image.the measurement parameters were compared with ANOVA analysis or Kruskal—Wallis H test between three groups,and receiver operating characteristic?ROC?curve was performed to access the value of differential diagnosis.Results:Enhanced CT with arterial and venous phase,group A and group B single-energy CT value difference was statistically significant?P<0.05?,the arterial phase at an energy value of 70kev?Z=-4.243?,The biggest difference between the two.Venous phase at the energy value of40kev?Z=-3.061?the difference between the two largest.Eff-Z,IC and K values of group A and group B were significantly different?P<0.05?compared with any other two groups in enhanced arterial phase and venous phase.However,the difference between group C and group A,group C and group B was not statistically significant?P>0.05?.There was no statistical significance in enhancing the WC value between the arterial phase and the venous phase among the three groups?P>0.05?.The ROC curve showed that the arterial phase CT_70keV of 60.90HU as the threshold of the metastatic lymph nodes and non-metastatic lymph nodes the sensitivity and specificity were 76%and 74%.the venous phase IC of 24.25 as the threshold of the metastatic lymph nodes and non-metastatic lymph nodes the sensitivity and specificity were 71%and80%.Conclusion:Spectrum CT imaging can help differential diagnosis of esophageal cancer and metastatic lymph nodes and provide a new diagnostic model to determine the origin and nature of lymph nodes.