Figure 5:

Scatterplot shows γ-H2AX foci with and without breast shielding during coronary CT angiography and ex vivo blood sample radiation at breast-tissue level. Excess DNA double-strand-break levels measured by γ-H2AX immunofluorescence before and after coronary CT angiography provide an estimation of radiation-induced DNA damage. Findings demonstrate no difference in DNA double-strand-break levels in blood samples exposed to ex vivo radiation at the breast-tissue level among women randomized to the use or absence of breast shielding (P = .61 between groups).