Estimates of Average Glandular Dose with Auto-modes of X-ray Exposures in Digital Breast Tomosynthesis

Objectives: the aim of this research was to examine the average glandular dose (agd) of radiationamong different breast compositions of glandular and adipose tissue with auto-modes of exposure factor selection in digital breast tomosynthesis. methods: this experimental study was carried out in the national cancer society, kuala lumpur, malaysia, between february 2012 and february 2013 using a tomosynthesis digital mammography x-ray machine. the entrance surface air kerma and the half-value layer were determined using a 100h thermoluminescent dosimeter on 50% glandular and 50% adipose tissue (50/50) and 20% glandular and 80% adipose tissue (20/80) commercially available breast phantoms (computerized imaging reference systems, inc., norfolk, virginia, usa) with auto-time, auto-filter and auto-kilovolt modes. results: the lowest agd for the 20/80 phantom with auto-time was 2.28 milligray (mgy) for two dimension (2d) and 2.48 mgy for three dimensional (3d) images. the lowest agd for the 50/50 phantom with auto-time was 0.97 mgy for 2d and 1.0 mgy for 3d. conclusion: the agd values for both phantoms were lower against a high kilovolt peak and the use of auto-filter mode was more practical for quick acquisition while limiting the probability of operator error.