Klinik für Strahlenheilkunde

Monte-Carlo-Simulationen und Dosimetrie für eine mit dem microDiamond-Detektor vermessene 192-Ir-HDR-Brachytherapiequelle

Our research group is currently investigating the feasibility of a diamond detector (microDiamond, PTW-Freiburg, Germany) to measure the dosimetry functions in a water phantom from a High Dose Rate (HDR) Ir 192 source used for clinical purposes. These dosimetry functions are mathematical functions which characterize each brachytherapy source and are used to determine the dose distribution around the source itself. They can be measured experimentally or determined with MC simulations. The objective of this study is to evaluate the suitability of the microDiamond detector for the dosimetric characterization of brachytherapy sources employed in clinical routine. With the help of the MC code MCNP6.1^TM (Los Alamos National Laboratory, Usa), we can obtain information about the performance of the microDiamond (energy dependence, volume effect) as well as about perturbation-effects related to the water phantom and to the experimental setup. The MC-based results are thus used to optimize the experimental setup for real measurements and to emend the experimental data from the aforementioned effects. The figure above, obtained from the MCNP6.1 visualization software, shows the source together with the microDiamond in a water phantom.