利用虚拟平扫降低冠状动脉CT血管造影辐射剂量的可行性研究  

Feasibility study of reducing the radiation dose on virtual non-contrast scanning in dual-layer spectral coronary CT angiography

作　　者：陈文萍 尹克杰 李茗[1] 康丽娜[2] 余鸿鸣[1] 梁静[1] 吴敏 Dar Kashif 陈杏彪 盛志洪 牡丹[1] Chen Wenping;Yin Kejie;Li Ming;Kang lina;Yu Hongming;Liang Jing;Wu Min;Kashif Dar;Chen Xingbiao;Sheng Zhihong;Mu Dan(Department of Radiology,Nanjing Drum Tower Hospital,Affiliated Hospital of Nanjing University Medical School,Nanjing 210008,China;Department of Cardiology,Nanjing Drum Tower Hospital,Affiliated Hospital of Nanjing University Medical School,Nanjing 210008,China;Department of Radiology,Tongren People′s Hospital,Guizhou Province,Guiyang 554300,China;Department of Cardiology,Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University,Nanjing 210008,China;Clinical Science,Philips Healthcare,Shanghai 200070,China)

机构地区：[1]南京大学医学院附属鼓楼医院医学影像科,南京210008 [2]南京大学医学院附属鼓楼医院心内科,南京210008 [3]贵州省铜仁市人民医院放射科,贵阳554300 [4]南京医科大学鼓楼临床医学院心内科,南京210008 [5]飞利浦医疗临床科研部,上海200070

出　　处：《中华放射医学与防护杂志》2022年第1期61-66,共6页Chinese Journal of Radiological Medicine and Protection

基　　金：中国博士后科学基金(2019M661804);江苏省博士后科学基金(2019k060);南京市医学科学技术发展基金(ZKX19018、QRX17057);南京鼓楼医院新技术发展基金(XJSFZJJ202026)。

摘　　要：目的探讨利用双层探测器光谱CT冠状动脉CT血管造影(CCTA)钙化积分的虚拟平扫成像(VNC)降低扫描辐射剂量的可行性。方法回顾性分析2019年3月至2020年8月在南京大学医学院附属鼓楼医院双层探测器光谱CT行CCTA扫描的122例患者资料。记录每位患者的CT容积剂量指数(CTDIvol)、剂量长度乘积(DLP)及有效剂量(E)。记录检查时间。在后处理工作站中, 基于CCTA的光谱基数据(SBI)生成VNC图像。2名医师分别独立评价左前降支(LAD)、左回旋支(LCx)、右冠状动脉(RCA)真实平扫(TNC)及VNC的钙化积分(CS;NC, CS;NC)并做Pearson相关性分析, 得到校正系数λ, 各分支校正系数分别记为λLAD、λLCx、λRCA, 总体冠状动脉(Total)的平均校正系数记为λAVG。校正后VNC的CS(CCS;NC)=λ× CS;NC。采用重复测量单因素方差分析比较CS;NC、CCS;NC的差异;采用Bland-Altman法分析评价CS;NC、CCS;NC一致性。结果获得CS平扫的辐射剂量为0.69 mSv。心电门控冠状动脉CTA扫描的辐射剂量为6.47 mSv, 总的辐射剂量为7.16 mSv。利用基于双层探测器光谱CT冠状动脉CTA的VNC图像替代TNC图像获得CS, 可省去CTA前的平扫, 减少10.6%的总辐射剂量及39%的检查时间。LAD、LCx、RCA及Total的CS;NC, CS;NC差异有统计学意义(t=6.75、5.33、4.99、6.60, P < 0.05), 相关性良好(R2=0.929、0.896、0.958、0.918, λ=2.18、1.18、2.15、2.07)。LAD和RCA的CS;NC、平均系数CCS;NC及分支系数CCS;NC的差异均无统计学意义(P > 0.05)。LCx的CS;NC、平均系数CCS;NC及分支系数CCS;NC差异有统计学意义(F=10.94, P<0.05)。组内两两比较:CS;NC与平均系数CCS;NC及平均系数CCS;NC与分支系数CCS;NC差异有统计学意义(t=3.21、3.43, P<0.05), LCx的CS;NC与及分支系数CCS;NC无统计学差异(P>0.05)。结论利用双层探测器光谱CT的VNC技术可以从CCTA图像中准确评价冠状动脉CS, 有望代替冠状动脉常规CT平扫, 从而有效降低患者辐射剂量及减少扫描Objective To investigate the feasibility of reducing the radiation dose on coronary artery calcium score(CS)of virtual non-contrast(VNC)scanning in dual-layer spectral coronary CT angiography(CCTA).Methods One hundred and twenty-two patients were examined on a dual-layer spectral detector CT scanner from March 2019 to August 2020.Volume CT dose index(CTDIvol),dose length product(DLP),effective dose(E)were all evaluated for each patient.CS was calculated from both true non-contrast(TNC)and VNC images for left anterior descending(LAD),left circumflex(LCx),right coronary artery(RCA),and the total coronary artery(Total)by two radiologists independently.Pearson′s correlation coefficient was calculated for measuring the association between variables.The correction coefficients of each branch(λLAD,λLCx,andλRCA)and the average correction coefficient(λAVG)of the total coronary artery were obtained.The calibrated calcium score(CCS_VNC)was equal toλmultiplied by CS_VNC.The CS_TNC and CCS_VNC were compared using repeated oneway analysis of variance test.Correlation analyses for CS_TNC and CCS_VNC and agreement evaluation with Bland-Altman-Plots were performed.Results The average effective doses in TNC,CCTA and total group were 0.69,6.47 and 7.16 mSv,respectively.The effective dose was reduced by 10.6%and the scan time was reduced by 39%while using VNC images.There were significant differences among the CS_TNC and CS_VNC of LAD,LCx,RCA and Total(t=6.75,5.33,4.99,6.60,P<0.05).Excellent correlations were observed between CS_VNC and CS_TNC(R2 values were 0.929,0.896,0.958,and 0.918;λvalues were 2.18,1.18,2.15,and 2.07,respectively).There were no significant statistically difference among the CS_TNC,CCS_VNCAVG,and CCS_VNCLAD/RCA of the LAD and RCA(all P>0.05).The difference was statistically significant among the CS_TNC,CCS_VNCAVG,and CCS_VNCLCx of the LCx(F=10.94,P<0.05).The paired comparison were performed in groups and the differences were statistically significant between the CS_TNC versus CCS_VNCAVGand CCS_VNCAVG ver

关 键 词：计算机体层成像 冠状动脉 血管钙化 辐射剂量 虚拟平扫 

分 类 号：R814.2[医药卫生—影像医学与核医学]