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

Abstract

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 2.11mGy and 0.85 to 2.15mGy for phantoms and patients, respectively. The novel methodology has a potential use for DBT equipment without stationary mode.