Characterisation of TLDs-200 and OSLDs at low X-ray energies and determination of eye lens dose, thyroid dose and mean glandular dose during standard mammography and tomosynthesis

The objective of this study was to characterise thermoluminescent (TLDs) and optically stimulated luminescent dosimeters (OSLDs) at low X-ray energies and estimate the eye lens (D_L), thyroid (D_T) and mean glandular (D_G) doses received during Full-Field Digital Mammography (FFDM) and Digital Breast Tomosynthesis (DBT). The dosimeters were characterised in mammography energies. D_L, D_T and D_G were estimated in FFDM and DBT mode taping dosimeters on the skin of the thyroid gland and on the left eye lens of an Alderson phantom. Dosimeters were also placed on the top of a NORMI PAS phantom simulating a compressed breast. The accuracy, precision and lower limit of detection (LLD) for TLDs and OSLDs were 5 and 8%, 6 and 3%, and 38 and 11 μSv, respectively. The linearity of the kerma response had an R² > 0.99 and energy dependence was lower than 40%. D_T ranged from 0.40 to 2.87 μGy for FFDM and 1.27 to 5.99 μGy for DBT. D_G was between 0.50 and 1.27 mGy for FFDM and 1.07 and 1.60 mGy for DBT. D_L was below the LLD. Dosimeters showed good performance. D_G values were lower than those found in the literature, whereas D_T value agreed with references. Differences between D_G and D_T determined with OSLDs and TLDs were lower than 10% and 200%. (authors)