Average Absorbed Breast Dose (۲ABD) to Mean Glandular Dose (MGD) Conversion Function for Digital Breast Tomosynthesis: A New Approach

Background: In this work a new method for the Mean Glandular Doseevaluation in digital breast tomosynthesis (DBT) is presented.Methods: Starting from the experimental-based dosimetric index, ۲ABD,which represents the average absorbed breast dose, the mean glandular doseMGD۲ABD was calculated using a conversion function of glandularity f(G),obtained through the use of Monte Carlo simulations.Results: f(G) was computed for a ۴.۵ cm thick breast: from its valueMGD۲ABD for different compressed breast thicknesses and glandularities wasobtained. The comparison between MGD۲ABD estimates and the dosimetricindex provided in the current dosimetry protocols, following the Dance'sapproach, MGD , showed a good agreement (<۱۰%) for all the analyzed breast Dancethicknesses and glandularities.Conclusion: The strength of the proposed method can be considered anaccurate mean glandular dose assessment starting from few and accessibleparameters, reported in the header DICOM of each DBT exam.

کلیدواژه ها:

Digital breast tomosynthesis ، breast dosimetry ، absorbed breast dose ، mean glandular dose ، average glandular dose