Estimating organ dose and specific effective dose in coronary artery CT angiography based on size-specific dose estimation
10.3760/cma.j.issn.0254-5098.2021.10.010
- VernacularTitle: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
- Author:
Zhuang NIE
1
;
Ziqiao LEI
;
Ming YANG
;
Jianming YU
Author Information
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
- Keywords:
Size-specific dose estimation;
CT angiography;
Coronary artery;
Organ dose;
Specific effective dose
- From:
Chinese Journal of Radiological Medicine and Protection
2021;41(10):778-783
- CountryChina
- Language:Chinese
-
Abstract:
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 CTDI vol, 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=1.2 X-6.4 ( R2=0.91, P<0.05, mean error 0.1%) for heart, Y=1.4 X-7.4 ( R2=0.91, P<0.05, mean error 7.9%) for breast, Y=0.89 X-4.6 ( R2=0.86, P<0.05, mean error 8.3%) for lung, and Y=0.36 X-1.8 ( R2=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=0.21 X-1.2 ( R2=0.92, P<0.05, mean error 0.2%) for men, Y=0.39 X-2.2 ( R2=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.
