| Objective:To explore the value of dual-energy CT energy spectral imaging in the differential diagnosis of metastatic lymph nodes and lymphoma of abdominal gastrointestinal tumors.Methods:Analyzed the energy data of the dual-energy CT arterial phase and venous phase in 17 patients with lymphoma and 17 patients with gastrointestinal malignant lymph node metastasis retrospectively,and obtained 40KeV-140KeV single-energy reconstruction images,respectively measuring the arteries of the two Single-energy CT values(CTAP,CTVP),iodine concentration（Iodine Concentration IC）,and effective atomic number（Zeff）at 40KeV-140KeV in the venous phase and venous phase,respectively,calculate the normalized iodine concentration（NIC）of both the arterial and venous phases,normalized effective atomic number（normalized Z value）,slope of the energy spectrum curve（λHu）.Two independent samples t-test analysis between groups showed significant statistical difference with P<0.05.Results:There were 48 lymphomas and 48 metastatic lymph nodes.In the range of40-140 KeV with the increase of single-energy KeV the CT values of the two lesions in the arterial phase and the venous phase gradually decreased,and the higher the single energy,the smaller the decrease of the CT value.There was a statistically significant difference in CT values between the two at 40-140 KeV（P<0.05）.The slopes of arterial and venous phases of metastatic lymph nodes and lymphomas were1.28±0.2 vs 1.84±0.24 and 1.57±0.28 vs 2.04±0.54,respectively.There were significant differences in the slopes between the two lymph nodes and the venous phase.The iodine concentrations in the arterial phase and venous phase were（1.06±0.24）mg/ml vs（1.25±0.21）mg/ml,（1.12±0.23）mg/ml vs（1.44±0.28）mg/ml,respectively;The atomic number was 7.94±0.16 vs 8.31±0.24,and the difference was statistically significant.Conclusion:Quantitative analysis of energy spectral CT imaging has certain clinical value in differential diagnosis of metastatic lymph nodes and lymphoma. |
