Optimal Parameters for Virtual Mono-Energetic Imaging of Liver Solid Lesions / 中国医学科学院学报

Objective To explore the optimal parameters for virtual mono-energetic imaging of liver solid lesions. Methods A retrospective analysis was performed on 60 patients undergoing contrast-enhanced spectral CT of the abdomen.The iodine concentration values of hepatic arterial phase images and the CT values of different mono-energetic images were measured.The correlation coefficient and coefficient of variation were calculated. Results The average correlation coefficients between iodine concentrations and CT values of hepatic solid lesion images at 40,45,50,55,60,65,and 70 keV were 0.996,0.995,0.993,0.989,0.978,0.970,and 0.961,respectively.The correlation coefficients at 40(P=0.007),45(P=0.022),50 keV (P=0.035)were higher than that at 55 keV,and the correlation coefficients at 40 keV(P=0.134) and 45 keV(P=0.368) had no significant differences from that at 50 keV.The coefficients of variation of the CT values at 40,45,and 50 keV were 0.146,0.154,and 0.163,respectively. Conclusion The energy of 40 keV is optimal for virtual mono-energetic imaging of liver solid lesions in the late arterial phase,which is helpful for the diagnosis of liver diseases.

Optimal Mono-energy in Mono-energetic Spectral Computed Tomography of Enhanced Renal Cortex in Cortical Phase Based on Iodine Concentration / 中国医学科学院学报

Objective To identify the optimal mono-energetic enhanced spectral CT for renal cortex in cortical phase based on the iodine concentration. Methods Fifty patients with normal renal function received the abdominal enhanced spectral CT examination.The iodine concentration and CT values of the multiple mono-energetic spectral images were measured on renal cortex in cortical phase,and the correlation between the iodine concentration and the CT values and the coefficient of variation(CV)were analyzed. Results The correlation analysis demonstrated that the correlation coefficient was 0.994,0.994,0.993,0.987,0.976,0.960,and 0.938 between mono-energetic spectral CT images(40-100 keV with interval 10 keV,respectively)and iodine concentration(all