Monte Carlo study of glandular dose distribution on radiological procedures for woman who has breast silicone implant

The silicone gel implant for breast have been, more and more, a common procedure among women of different ages around the world. That way it is important to know how it can affect the dose on sensitive tissues around the implanted silicone. On this work we are studying the influence on absorbed dose distribution map into the patient, especially on tissues close to the silicone implant for diagnostic radiological procedures comparing a map of dose distribution for voxel model simulating patients with and without breast silicone implant. So three models of woman trunk considering were built considering the breasts with and without silicon implant. The three developed models were introduced into Geant4 code (version 9.2.p01) and were simulated three different parallel beam sources: frontal, lateral and rotational. The photons energy were sorted considering the distribution that represents the x-radiation spectra emitted by a tungsten target and considers additional filtration of 3 mmAl at difference peak tensions. For all the studied cases the simulations considering the anterior-posterior exposures positioning of silicone implant produce a significant increase on glandular dose. For peak tension of 80 kVp was calculated having a mean increase on glandular dose of 12% for the both breast simulated with silicone implant over and under the pectoral muscle. This difference decrease when the kVp increase been registered a mean value of 4, 5% for the peak tension of 120 kVp. There was no significant difference for the absorbed glandular dose calculated for the lateral positioning exposure, been presented differences always under 3, 5% for 80 kVp spectra. For higher kVp the differences presented were inferior to the statistical fluctuation due the simulation process. As conclusion the simulations realized in this work shown that the presence of silicone implant can, considering some cases, increase significantly the glandular dose due the backscattering.