Radiation dose and cancer risk in retrospectively and prospectively ECG-gated coronary angiography using 64-slice multidetector CT

Abstract

This study aimed to estimate the radiation dose and cancer risk to adults in England, the USA and Hong Kong associated with retrospectively and prospectively electrocardiogram (ECG)-gated coronary computed tomography angiography (CTA) using currently practised protocols in Hong Kong. The doses were simulated using the ImPACT spreadsheet. For retrospectively ECG-gated CTA with pitches of 0.2, 0.22 and 0.24, the effective doses were 27.7, 23.6 and 20.7 mSv, respectively, for males and 23.6, 20.0 and 18.8 mSv, respectively, for females. For prospectively ECG-gated CTA, the effective dose was 3.7 mSv for both males and females. A table of lifetime attributable risks (LAR) of cancer incidence was set up for the English population for the purpose of estimating cancer risk induced by low-dose radiation exposure, as previously reported for US and Hong Kong populations. From the tables, the LAR of cancer incidence for a representative 50-year-old subject was calculated for retrospectively ECG-gated CTA to be 0.112% and 0.227% for English males and females, respectively, 0.103% and 0.228% for US males and females, respectively, and was comparatively higher at 0.137% and 0.370% for Hong Kong males and females, respectively; for prospectively ECG-gated CTA, the corresponding values were calculated to be 0.014% and 0.035% for English males and females, respectively, and 0.013% and 0.036% for US males and females, respectively, and again were higher at 0.017% and 0.060% for Hong Kong males and females, respectively. Our study shows that prospectively ECG-gated CTA reduces radiation dose and cancer risks by up to 87% compared with retrospectively ECG-gated CTA.

Risk of radiation-induced malignancies from CT scanning in children who underwent shunt treatment before 6 years of age: a retrospective cohort study with a minimum 10-year follow-up

“…6,8,30 Multiple authors have then extrapolated the expected risk of future cancer from CT scanning by equating the phantom model doses to the known risk reported in the BEIR VII report. 1,3,7,9,11,12,14,18,21,22,28,34 These models predict an alarming number of future cancers. Berrington de González et al predicted 29,000 future cancers and 14,500 future deaths in the US caused by 1 year of CT scanning.…”

“…10 Various models and anthropomorphic phantom simulations provide estimates for the effective radiation dose to organs based on the type of CT scanning study. 3,7,9,14,18 Authors have then correlated the radiation dose from simulations to similar doses from the BEIR VII report to calculate a mathematical estimate of the lifetime attributable risk of cancer development.…”

Role of Noninvasive Testing in the Clinical Evaluation of Women With Suspected Ischemic Heart Disease

“…46 Diagnostic invasive angiography results in an exposure of ≈7 mSv. 38 The estimated cancer risk after CCTA 34,47 or MPI 37 is in the range of 3 to 8 affected people per 10 000 tested. Importantly, estimated cancer risk may be overestimated among symptomatic women with reduced life expectancy.…”

Inaccuracy in geographic terms

“…The Editor -Sir, I enjoyed reading the paper ''Radiation dose and cancer risk in retrospectively and prospectively ECGgated coronary angiography using 64-slice multidetector CT'' [1], published in the British Journal of Radiology.…”