Posted on 15 January 2014
CEA LIST researchers have recently completed an out-of-field dosimetry study to help better understanding of the iatrogenic effects of modern external radiotherapy treatment protocols.
The researchers characterized the doses received by normal tissues outside of the tumor due to diffusion in the collimators and in the patient’s body and also to shield leakage.
Measurements taken at France’s national metrology lab for ionizing radiation, LNHB (Laboratoire national Henri-Becquerel), using a cavity ionization chamber, were used to calibrate passive dosimeters (thermoluminescent, photoluminescent, and optically-stimulated luminescence or OSL). Large numbers of the dosimeters were placed in an anthropomorphic phantom to mathematically reconstruct dose distributions in 3D. The data produced were used to validate the out-of-field dose simulator developed by DM2I/LM2S using the Penelope Monte Carlo code.
The researchers are now investigating direct 3D measurement using dosimetric gel to further improve the method.
