基于体型特异性剂量估算值推算冠状动脉CT血管成像中患者器官剂量和个体有效剂量的可行性研究  

Estimating organ dose and specific effective dose in coronary artery CT angiography based on size-specific dose estimation

作　　者：聂壮 雷子乔[1] 杨明[1] 余建明[1] Nie Zhuang;Lei Ziqiao;Yang Ming;Yu Jianming(Department of Radiology,Union Hospital of Tongji Medical College of Huazhong University of Science and Technology,Hubei Province Key Laboratory of Molecular Imaging,Wuhan 430022,China)

机构地区：[1]华中科技大学同济医学院附属协和医院放射科分子影像湖北省重点实验室,武汉430022

出　　处：《中华放射医学与防护杂志》2021年第10期778-783,共6页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的探讨将体型特异性剂量估算值(SSDE)用于估算冠状动脉CT血管成像(CTA)中患者器官剂量和个体有效剂量的可行性。方法回顾性连续纳入冠状动脉CTA患者421例,均于第3代双源Force型CT采用前瞻性心电门控触发轴扫协议检查。通过Radimetrics计算患者水当量直径以计算每位患者的SSDE;使用Monte Carlo模拟估算患者扫描范围内器官的吸收剂量包括心脏、肺、肝和乳腺。使用国际放射防护委员会(ICRP)103报告的器官敏感加权系数,将患者主要敏感器官的剂量加权求和计算个体有效剂量。使用线性相关分析验证SSDE与器官剂量及个体有效剂量的相关性,并推导基于SSDE估算器官剂量和个体有效剂量的转换系数。使用平均差值比评价该估算方法的准确性。结果容积CT剂量指数(CTDIvol)为(16.8±8.7)mGy,SSDE为(20.8±8.8)mGy,个体有效剂量为(4.4±2.9)mSv。基于SSDE估算器官剂量的线性拟合公式为:心脏Y=1.2X-6.4(R^(2)=0.91,P<0.05,平均误差0.1%);乳腺Y=1.4X-7.4(R^(2)=0.91,P<0.05,平均误差7.9%);肺脏Y=0.89X-4.6(R^(2)=0.86,P<0.05,平均误差8.3%);肝脏Y=0.36X-1.8(R^(2)=0.64,P<0.05,平均误差-17.9%)。基于SSDE估算个体有效剂量的线性拟合公式为:男Y=0.21X-1.2(R^(2)=0.92,P<0.05,平均误差0.2%);女Y=0.39X-2.2(R^(2)=0.93,P<0.05,平均误差1.7%)。结论在冠状动脉CTA检查中通过SSDE和相应的转换系数可估算被照射器官吸收剂量和个体有效剂量,将有助于在临床工作中实现患者辐射剂量及风险的个性化评估和精准管理。Objective To study the feasibility that using size-specific dose estimation(SSDE)to estimate organ dose and effective dose in coronary CT angiography(CTA).Methods Totally 421 consecutive patients with coronary artery CTA were included and retrospectively analized.All patients were scanned using the 3rd generation dual-source Force CT with prospectively ECG gated axis scan mode.The size specific dose estimation(SSDE)for each patient was conducted by calculate water equivalent diameters with Radimetrics.The organ doses of heart,lung,liver and breast,were estimated with Monte Carlo method.Patient-specific effective dose was calculated as a weighted sum of simulated organ doses with the coefficients from ICRP 103.Linear correlation analysis was used to validate the relationship between SSDE and organ doses as well as effective dose,and to derive coefficients for patient specific dose estimation.The mean error rate was used to evaluate estimation accuracy.Results The CTDIvol,SSDE and effective dose were(16.8±8.7)mGy,(20.8±8.8)mGy and(4.4±2.9)mSv,respectively.The linear fitting formula for estimating organ dose based on SSDE were:Y=1.2X-6.4(R^(2)=0.91,P<0.05,mean error 0.1%)for heart,Y=1.4X-7.4(R^(2)=0.91,P<0.05,mean error 7.9%)for breast,Y=0.89X-4.6(R^(2)=0.86,P<0.05,mean error 8.3%)for lung,and Y=0.36X-1.8(R^(2)=0.64,P<0.05,mean error-17.9%)for liver.The linear fitting formula for estimating the individual effective dose based on SSDE were:Y=0.21X-1.2(R^(2)=0.92,P<0.05,mean error 0.2%)for men,Y=0.39X-2.2(R^(2)=0.93,P<0.05,mean error 1.7%)for women.Conclusions In coronary artery CTA,the absorbed dose of the organs and patient specific effective dose could be estimated with SSDE and the corresponding conversion coefficients,which will help to achieve personalized assessment and precise management of patient radiation dose and risk in clinical practice.

关 键 词：体型特异性剂量估算值 CT血管成像 冠状动脉 器官剂量 个体有效剂量 

分 类 号：R816.2[医药卫生—放射医学]