The calculation of dose enhancement close to platinum implants for skull radiography.

Materials with high atomic numbers experience the occurrence of the photoelectric effect when they are irradiated by low energy photons. A short range dose enhancement, due to the dominant photoelectric effect, close to platinum implants (Z = 78) in diagnostic radiography cannot be easily measured experimentally. The enhanced dose may increase the risk for adverse health effects from cancer or may damage vital brain structures close to the high atomic number implants. In the present work, Monte Carlo simulation using the LSCAT version of PRESTA EGS4 was employed to investigate the resulting dose enhancements. The results show that the highest estimated dose enhancement of 79% for brain tissues close to platinum implants was calculated for 65 kV x-ray energy and 180% for 120 kV x-ray energy.