摘要
目的:探讨正弦图迭代重建(SAFIRE)及滤波反投影(FBP)重建分别联合双能量线性融合(LB)技术和非线性融合(NLB)技术对双源CT肺动脉成像的图像质量、栓子检出率及辐射剂量的影响。方法:将临床怀疑肺栓塞(PE)并行双源CT双能量肺动脉成像的170例患者随机分为A组(90例,80kV/Sn140kV)和B组(80例,100kV/Sn140kV),分别采用FBP和SAFIRE对A组数据进行重建,然后利用双能量优化对比软件进行后处理,共获得4组图像:FBP+LB(A1组)、FBP+NLB(A2组)、SAFIRE+LB(A3组)、SAFIRE+NLB(A4组)。B组采用FBP重建获得LB图像。对图像质量进行客观评价[肺动脉CT值、背景噪声(BN)、SNR及CNR]和主观评分,同时对有无栓子、栓子的位置进行诊断并记录。比较5组的图像质量、栓子检出情况及不同管电压下的辐射剂量。结果:A1~A4组的各级肺动脉CT值均高于B组。A1组的BN明显高于B组,A2~A4组的BN明显低于B组,其中A4组BN较B组降低约44.5%。A1组与B组间肺动脉的SNR及各叶肺动脉的CNR的差异均无统计学意义(P>0.05),但A2~A4组各级肺动脉的SNR和CNR均高于B组,其中以A4组最高。5组图像质量主观评分的差异无统计学意义(P>0.05),两位观察者间的一致性非常好。A组中共检出42个中央型栓子和98个周围型栓子,B组中分别检出41个和56个。5组中对中央型栓子的检出敏感度及特异度均为100%,对周围型栓子的检出敏感度及特异度则有所不同:A1~A4组和B组分别为73.3%及93.3%、83.4%及95%、80%及93.3%、90%及96.7%、82.8%及92.2%,ROC曲线下面积(AUC)分别为0.85、0.91、0.88、0.94和0.88。两位观察者对中央型及周围型栓子的检出一致性非常好。A组的有效辐射剂量(ED)较B组降低约6.9%。结论:SAFIRE重建及双能量NLB技术均可降低双源CT肺动脉成像的图像噪声,提高图像质量及栓子检出率,同时降低辐射剂量,两者联合应用的价值更大。
Objective:To investigate the effects of sinogram affirmed iterative reconstruction(SAFIRE)and filtered back projection(FBP)reconstruction combined with dual-energy linear blen-ding(LB)or nonlinear blending(NLB)on the image quality,embolus detection rate and radiation dose in dual-source CT pulmonary angiography.Methods:170 patients with suspected pulmonary embolism(PE)who undergone dual-source CT dual-energy pulmonary angiography were randomly divided into group A(n=90;80/Sn140kV)and group B(n=80;100/Sn140kV).FBP or SAFIRE technique and dual energy optimization contrast software were used to reconstruct the data of group A,and four sets of images were obtained:FBP+LB(group A1),FBP+NLB(group A2),SAFIRE+LB(group A3)and SAFIRE+NLB(group A4).In group B,LB images were obtained with FBP reconstruction.Objective evaluation using quantification indexes(including pulmonary artery CT value,background noise,signal-to-noise ratio and contrast-to-noise ratio)and subjective score were performed on the image quality.Meanwhile,the presence and location of embolus were diagnosed and recorded.The image quality,embolus detection and radiation dose under different tube voltages were compared among the five groups.Results:CT values of all pulmonary arteries in group A1 to group A4 were higher than those in group B.The background noise(BN)of group A1 was significantly higher than that of group B,while the values of group A2 to A4 were significantly lower than that of group B,the BN of group A4 was reduced by 44.5%compared with group B.There was no significant diffe-rence in SNR of all pulmonary arteries and CNR of all lobar pulmonary arteries between group A1 and group B(P>0.05),but SNR and CNR of all pulmonary arteries in group A2 to group A4 were higher than that of group B,in which group A4 was the highest.There was no significant difference in the subjective score of image quality among the five groups(P>0.05)with excellent inter-observer agreement.42 central emboli and 98 peripheral emboli were detected in group A,41 central embo
作者
罗显丽
孙铝
王凤
金开元
李邦国
LUO Xian-li;SUN Lv;WANG Feng(Department of Radiology,the Affiliated Hospital of Zunyi Medical University,Guizhou 563003,China)
出处
《放射学实践》
北大核心
2020年第12期1618-1623,共6页
Radiologic Practice
基金
遵义医学院附属医院硕士科研启动基金项目[院字(2017)56号]
遵义市科技局联合基金项目[遵义科合社(2018)89号]
遵义市科技局基金引导项目[遵义市科合HZ字(2019)59号]。
关键词
双能量
正弦图迭代重建
非线性融合
CT肺动脉成像
图像质量
辐射剂量
Dual-energy
Sinogram affirmed iterative reconstruction
Nonlinear blending
Computed tomography pulmonary artery angiography
Image quality
Radiation dose
