瞬时管电压切换单源双能CT物质分离技术定量评估肝脏脂肪变的体模研究  

Quantification of hepatic steatosis with fast-kilovolt-peak switching dual-energy CT imaging and material decomposition technique:an in vitro experiment study

作　　者：谢婷婷[1] 黎永滨[2] 严帅[1] 何冠勇 郭英 成官迅[1] XIE Ting-ting;LI Yong-bin;YAN Shuai(Department of medical imaging,Peking University Shenzhen Hospital,Guangdong 518036,China;不详)

机构地区：[1]北京大学深圳医院医学影像科,广东518036 [2]北京大学深圳医院超声影像科,广东518036 [3]GE中国CT影像研究中心,广州510623

出　　处：《放射学实践》2021年第11期1346-1350,共5页Radiologic Practice

基　　金：北京大学深圳医院科研基金资助课题(JCYJ2020007)。

摘　　要：目的:探讨瞬时管电压切换单源双能CT物质分离技术量化评估肝脏脂肪变的可行性。方法:采用256排单源双能CT,采用能谱扫描模式,对2个肝脏脂肪变体外模型(模型A不含铁、模型B含铁,脂肪体积分数为0%~50%,铁浓度分别为5、20、25 mg/mL)分别进行扫描。重建脂肪(水)基物质对图像,记录虚拟脂肪浓度值(VFC)。对3组管电流(200、320、485 mA)下相应VFC与实际肝脂肪体积分数(FVF)的相关性行Spearmen相关分析,并拟合线性方程。结果:模型A在不同管电流下,肝脂肪体积分数10%~40%相应VFC与FVF均呈线性正相关(r=0.885,P<0.001),拟合线性方程斜率为0.072,截距为27.138;但肝脂肪体积分数0%~40%相应VFC与FVF无相关性(r=0.371,P=0.173)。在相同脂肪体积分数的情况下,模型B内铁浓度越高、相应VFC值越低。结论:在体外实验上,瞬时管电压切换单源双能CT物质分离技术可用于脂肪体积分数为10%~40%的肝脂肪定量评估,铁的存在导致VFC测值降低。Objective:To evaluate liver fat quantification by using Fast-Kilovolt-Peak switching dual-energy CT imaging and material decomposition technique.Methods:Two dual-energy CT phantoms with fat inserts[model A(iron-free),model B(iron-contained),fat volume fraction was 0%to 50%,iron concentrations were 5,20,25mg/mL]were prepared and scanned by 256-slice DECT.After CT scan,fat(water)images were reconstructed,virtual fat concentrations(VFC)were measured and the correlation between VFC and titrated fat volume fraction(FVF)were analyzed by Spearman's correlation and linear regression analysis.Results:Significant positive linear correlations were found between VFC and FVF in the absence of iron(model A)when the FVF were 10%to 40%(all the r values were 1.000,P values were 0.000),the slopes and the intercepts were 0.072 and 27.138,respectively.However,there was no significant difference between VFC and FVF when the FVF were 0%to 40%(all the r values were 1.000,P values were 0.000).At the same fat volume fractions,the higher the iron concentrations were,the lower the corresponding VFC values were in model B.Conclusion:The fast-kilovolt-peak switching dual-energy CT imaging and material decomposition technique can be used for liver fat quantification when the FVF were 10%to 40%in vitro.The coexisting of iron decrease the value of VFC measurements.

关 键 词：体层摄影术 X线计算机 物质分离 肝 脂肪 铁 

分 类 号：R814.42[医药卫生—影像医学与核医学] R575.5[医药卫生—放射医学]