不同基物质图像的选择对瞬时管电压切换单源双能CT物质分离技术量化评估肝脏铁过载的影响  

Effect of Different Substrate Image Selection on Quantitative Assessment of Liver Iron Overload by Transient Tube Voltage Switching Single-source Dualenergy CT

作　　者：戚玉龙[1] 谢婷婷[1] 黎永滨[2] 冯飞[1] 张辉[1] 成官迅[1] QI Yu-long;XIE Ting-ting;LI Yong-bin;FENG Fei;ZHANG Hui;CHENG Guan-xu(Medical Imaging Center,Peking University Shenzhen Hospital,Shenzhen 518036,Guangdong Province,China;Department of Ultrasound,Peking University Shenzhen Hospital,Shenzhen 518036,Guangdong Province,China)

机构地区：[1]广东省北京大学深圳医院医学影像科,广东深圳518036 [2]广东省北京大学深圳医院超声科,广东深圳518036

出　　处：《中国CT和MRI杂志》2021年第6期4-7,共4页Chinese Journal of CT and MRI

摘　　要：目的探讨不同基物质图像的选择对瞬时管电压切换单源双能CT物质分离技术量化评估肝脏铁过载的影响。方法取25只健康SD大鼠的新鲜肝组织全部制成匀浆液,与右旋糖酐铁、脂肪混合后配制成肝脏铁沉积模型(模型A不含脂,模型B含脂,脂肪体积百分比分别为7.5%、15%),并置入标准体模中扫描。应用256排单源双能CT扫描仪,选择能谱模式扫描体模,管电压80、140k Vp瞬时切换,管电流分别为200、320、485。重建铁(水)、铁(脂肪)基物质对图像,记录虚拟肝铁浓度值(VIC铁(水)、VIC铁(脂肪))。对VIC与肝铁浓度(LIC)的相关性行Spearmen分析,并拟合线性方程。结果在不同管电流下,模型A相应的VIC铁(水)、VIC铁(脂肪)与LIC均呈线性正相关(r值均为1.00, P值均为0.00),拟合线性方程斜率分别为1.076~1.104、1.083~1.100,截距分别为-1.193~-1.602、-10.078~-10.762;模型B相应的VIC铁(水)、VIC铁(脂肪)与LIC均呈线性正相关(r值均为1.00, P值均为0.00),拟合线性方程斜率分别为1.582~1.721、1.520~2.127,截距分别为-10.509~-13.438、-15.869~-35.677;模型A和模型B在同一LIC水平,VIC铁(脂肪)值总大于VIC铁(水)值。结论不同基物质图像的选择对瞬时管电压切换单源双能CT物质分离技术肝铁浓度测定存在影响,选择铁(脂肪)基物质图像将高估肝铁浓度。Objective To investigate the influence of post-reconstruction algorithm of material decomposition(MD)images on the quantification of liver iron overload using fast-kilovolt-peak switching dual-energy CT imaging and material decomposition technique.Methods The fresh liver tissue of 25 healthy SD rats were prepared into homogenate,mixed with dextran and fat to make the liver iron deposition phantom(phantom A was fat-free,phantom B was fat-contain with fat volume fraction of 7.5%and 15%).Scanned the phantom by using a single-source DECT scanner with GSI mode,and the tube voltage was 80 and 140 kVp fast switching,the tube current was 200 mA,320 mA,and 485 mA,respectively.The MD images of iron(water)and iron(fat)were reconstructed,and the virtual iron concentration(VIC)values(VICiroe(water)and VICiron(fat))were recorded.The correlation between VIC and the actual liver iron concentration(LIC)was analyzed by Spearman correlation analysis and linear regression.Results The measurements of VICiroe(water),VICiron(fat)and LIC in model A are linearly positively correlated(all r values were 1.00,P-value were 0.00),the slope of the fitting linear equation is(1.076 to 1.104),(1.083 to 1.100)respectively,and the intercept is(-1.193 to-1.602)and(-10.078 to-10.762)respectively.The measu rements of VICiroe(water),VICiroe(fat)and LIC in model Bare linea rly positively correlated(all r values were 1.00,P value were 0.00),the slopes of the fitting linear equation are(1.582 to 1.721),(1.520 to 2.127)respectively,and the intercepts are(-10.509 to-13.438)and(-15.869 to-35.677)respectively.At the same level of LIC,the VIC iron(fat)measurements are always greater than the VIC iron(water)measurements.Conclusion The choice of different postreconstruction algorithm of material decomposition images,influences on the quantification of liver iron concentration by using fast-kilovolt-peak switching dual-energy CT imaging and material decomposition technique.The choice of iron(fat)MD images led to the overestimation of LIC.

关 键 词：体层摄影术 X线计算机 物质分离 肝 脂肪 铁 

分 类 号：R812[医药卫生—放射医学] R322.47[医药卫生—临床医学]