Study On Activity Of Marginal Zone Of Hepatic Alveolar Echinococcosis By Revolution CT Spectral Imaging

Objectives:To investigate the value of CT spectral imaging in evaluating the activity of hepatic alveolar echinococcosis（HAE）by comparing the relationship between the maximum standard uptake value(SUV_max)of ¹⁸F-FDG PET,Microvessel density（MVD）and quantitative iodine concentrations（IC）.Methods: This study including 32 patients with HAE who confirmed by pathology and underwent abdominal GSI three phase enhanced scan and PET/CT examination.The obtained spectral data was post-processed by GSI view software.The CT value and iodine concentrations of regions of interest（ROI）in liver parenchyma,marginal area,inside the lesion were measured at each single energy of 40-140kev（energy interval 10kev）;draw the spectral curve and calculate the slope of the spectrual curve [k=(HU_40kev-HU_90kev)/50].According to the position of the spectral CT,the SUV_maxof the ROI in the three different regions were measured,and the MVD counts of the ROI as well.Univariate analysis of variance was used to compare the differences in the slope of the spectral curve,IC,SUV_max,and MVD in three different areas.The correlation between quantitative IC,SUV_max,and MVD was evaluated using pearson correlation coefficient.Results:1、The CT value of three different areas of the HAE at each single energy decreases with the increase of kev during the arterial phase,portal vein phase,and venous phase,with the most significant decrease between 40-90 keV;the slope of the spectral curve between the three different regions is significantly different（P<0.001）.2、There were significant differences in the comparison of IC,SUVmax,and MVD in three different areas of the lessions（P<0.001）.3、The IC,SUV_max,and MVD of the marginal zone of the lesion had a significant positive correlation in the three phase enhanced scan（r₁=0.722,r₂=0.767,P﹤0.001）,and the vein phase was most significant.Conclusion:1、The spectal curves of HAE in three different areas is different,which can provide valuable information for distinguishing different areas of HAE.2、The IC of spectral CT has a good correlation with SUV_maxand MVD,which can non-invasively reflect the blood supply status and evaluate the activity of HAE.