前置自适应统计迭代重建技术对胸部CT平扫的辐射剂量及图像质量的影响  

Effect of pre-selected ASiR-V level on radiation dose and image quality of chest CT

作　　者：王立环 顾文豪[1] 丁佐运 郁一凡 王彩虹 许大波[1] WANG Lihuan;GU Wenhao;DING Zuoyun;YU Yifan;WANG Caihong;XU Dabo(Imaging Center,the First People's Hospital of Taicang,Taicang,Jiangsu Province 025400,China)

机构地区：[1]太仓市第一人民医院影像中心,江苏太仓025400

出　　处：《实用放射学杂志》2019年第1期122-125,共4页Journal of Practical Radiology

摘　　要：目的 探讨不同前置多模型的迭代重建技术(ASiR-V)比例对胸部CT平扫的辐射剂量、图像质量影响。 方法 81例患者均采用256排CT (Revolution,GE Healthcare)联合ASiR-V完成胸部平扫;测量所有纵隔窗脊柱两侧肌肉的噪声(SD)值,取SD值的平均值作为噪声;记录容积CT剂量指数(CTDIvol),并计算有效辐射剂量(ED)值;由2名放射科医师对图像质量进行主观评分(5分制)。 结果 ①ED与前置ASiR-V百分比率成负相关,相关系数r=-0.987,ASiR-V预设值60%时的平均ED值为(2.38±1.08) mSv,比ASiR-V预设值0%时(7.44±2.61) mSv的剂量降低68%。②噪声(SD值)与前置ASiR-V的百分比率成正相关,相关系数r=0.987,ASiR-V预设值60%时图像噪声(13.02±3.35)比ASiR-V预设值0%(9.49±1.38)升高27%。随着ASiR-V的提高,图像质量肉眼观察未见明显伪影。 结论 ASiR-V在保证图像质量的情况下能有效地降低辐射剂量,但会增加图像噪声。Objective To investigate the effect of different pre-selected adaptive statistical iterative reconstruction Veo(ASiR-V) level on radiation dose,image quality of chest CT.Methods 81 patients were enrolled in our study,all the patients underwent chest CT scan on a 256-detector row CT (Revolution,GE Healthcare)with ASiR-V technique.The SD values of the muscle of both sides of the spine were measured,the average SD value was regarded as image noise.The volume CT dose index (CTDIvol)were recorded,and effective radiation dose (ED)were calculated.Two radiologists independently evaluated the diagnostic quality of the images with 5-point quality score.Results ①The ED was negatively correlated with the pre-ASiR-V percentage(r=-0.987).The average ED for the pre-ASiR-V 60% was (2.38±1.08)mSv,lower than the pre-ASiR-V0%(7.44±2.61)roSy with a reduction by 68%.②The SD was positive correlated with the pre-ASiR-V percentage(r=0.987).The average image noise of pre-ASiR-V60 % was (13.02±3.35), higher than the pre-ASiR-V0%(9.49±1.38)with a increase by 27%.As the pre-ASiR-V increased that all the images had acceptable diagnostic image quality.Conclusion Pre-ASiR-V technique can effectively reduce the radiation dose and maintains image quality as the same time,but ASiR-V increases image noise.

关 键 词：多模型的迭代重建技术 辐射剂量 噪声指数 计算机体层成像 

分 类 号：R816.4[医药卫生—放射医学] R814.42[医药卫生—临床医学]