Comparison among homogeneous models and a voxel model on mammography: A Monte Carlo study using the GEANT4 code

The aim of this work is to compare the dosimetric data and the photon fluency in three positions among different homogeneous models to a voxel model. Were simulated the mammographic dosimetric homogeneous models and a breast voxel model which represents 4.0 cm compressed woman breast, with 50% of glandular tissue. Were simulated the photon spectra of Mo-30Mo from 26 kVp up to 34 kVp; and Mo-25Rh from 26 kVp up to 34 kVp characterized by the HVL values. For all techniques simulated the normalized glandular dose was superestimated by the BR12 homogeneous models and underestimated by PMMA homogeneous models comparing to voxel model. Among the models studied was the model proposed by Dance that presented a behavior similar to voxel model, however it underestimates all the DgN.