DOSIMETRY IN DIGITAL BREAST TOMOSYNTHESIS: COST-EFFICIENT APPROACH FOR THE SOUTH AMERICAN PERSPECTIVES

The measurement of air kerma in air (Kair) to estimate average glandular dose (AGD) received during digital breast tomosynthesis (DBT) studies is sometimes a difficult task. In this work, a novel methodology was implemented to measure Kair and half-value layer while the X-ray tube is rotating. A low economic cost support (LCS) was built to place aluminium sheets and a calibrated dosemeter. Three Fujifilm Innovality equipment were used and two dosemeters calibrated on W-Al energies. Validation of the new methodology was made against standard scheme and it was applied to estimate AGD for 300 patients and 7 phantoms. Validation analysis was satisfactory. The difference in the AGD calculated with the LCS and DICOM Header was lower than ±10%. AGD values ranged from 0.77 to 2.11 mGy and 0.85 to 2.15 mGy for phantoms and patients, respectively. The novel methodology has a potential use for DBT equipment without stationary mode.