Validation of a modified PENELOPE Monte Carlo code for applications in digital and dual-energy mammography

Abstract

The presence and morphology of microcalcification clusters are the main point to provide early indications of breast carcinomas. However, the visualization of those structures may be jeopardized due to overlapping tissues even for digital mammography systems. Although digital mammography is the current standard for breast cancer diagnosis, further improvements should be achieved in order to address some of those physical limitations. One possible solution for such issues is the application of the dual-energy technique (DE), which is able to highlight specific lesions or cancel out the tissue background. In this sense, this work aimed to evaluate several quantities of interest in radiation applications and compare those values with works present in the literature to validate a modified PENELOPE code for digital mammography applications. For instance, the scatter-to-primary ratio (SPR), the scatter fraction (SF) and the normalized mean glandular dose (DgN) were evaluated by simulations and the resulting values were compared to those found in earlier studies. Our results present a good correlation for the evaluated quantities, showing agreement equal or better than 5% for the scatter and dosimetric-related quantities when compared to the literature. Finally, a DE imaging chain was simulated and the visualization of microcalcifications was investigated.