MEAN GLANDULAR DOSE ESTIMATION FOR DIGITAL AUGMENTATION MAMMOGRAPHY

COUTO, L.S (HC- UFG), FREITAS-JUNIOR, R. (HC- UFG), CORRÊA, R.S. (CNEN- GO), PEIXOTO, J.E. (INCA- RJ), ALMEIDA, C.D. (IRD-RJ), LAUAR, M.V. (Clinica São Marcelo- GO), RODRIGUES, D.C.N. (HC- UFG), SOARES, L.R. (HC-UFG)

 

Hospital das Clínicas- Dep. Mastologia- UFGTo estimate the mean glandular dose (MGD) received by patients with breast implants undergoing screening mammography A retrospective study was carried out to evaluate the radiographic techniques established for the production of 335 woman mammography with augmented breasts performed in a digital equipment. A total of 2680 images, half in standard (STAND) without implant displacement maneuver and half with posterior implant displacement maneuver (ID), for the craniocaudal (CC) and medio-lateral oblique (MLO) view, being four views in each breast. Effective tube current, peak kilovoltage, MGD and breast thickness were collected from each produced image as well the implant position and breast density. The MGD was estimated in each breast and it was verified if the position of the implant, breast density and breast thickness influenced the MGD The average MGD in the right breast was 9.74 ± 0.56 mGy and in the left breast 9.83 ± 0.65 mGy. Stratifying by view, the statistical analysis showed no significant difference of MGD according to breast laterality, in both STAND and ID views. It was verified that the retroglandular position was the most frequent 84.8% in the study population and that the implant position does not interfere in MGD. MGD increases according to breast density with p = .000 in the right breast and p = .002 in the left breast. The MGD in the STAND views decrease as the compressed breast thickness increases and in the ID views the MGD increases as the thickness increases. The MGD is widely accepted as the most appropriate measurement for predicting the risk of radiation-induced cancer. In our study the MGD in augmentation mammography exceeds the recommended internationally, being the greater contribution coming from the STAND views. The radiation dose as expected was higher in dense breasts.Mammography, Breast Augmentation, Radiation Protection