Mean glandular dose

In mammography D_G is the mean absorbed dose in the glandular tissue of the breast. Glandular tissue is the radiosensitive tissue of the breast. D_G is calculated from either the incident air kerma (K_a,i) or the entrance-surface air kerma (K_a,e) used for the specific mammography examination. The conversion from K_a,i to D_G is a function of beam quality (i.e. half value layer), anode material, filtration, breast thickness, and breast composition. The conversion from K_a,e to D_G is a function of all these factors as well as adjustment for the backscatter factor from breast tissue. D_G is also called ‘average glandular dose’ (AGD) (measured in mGy).

(ICRP Publication 135, 2017)

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