A PHANTOM TO STUDY THE EFFECTS OF METALLIC PROSTHESES IN RADIOTHERAPY BY GEL DOSIMETRY

摘要

Recent advances in radiotherapy have improved conformation of dose, delivering high dose to the tumor with minimal damage to normal tissue. Closely related to this advance is the need for improved verification of dose distributions. In this regard, the use of polymeric gel dosimeters allows dosimetry in 3D. The aim of our work is to study prostate treatments and the influence of metallic femoral prosthesis in dose distribution. The presence of metallic prosthesis in the femur and pelvis, which is common in the elderly, is a confounding factor for dose measurement. In this study, a phantom of an adult pelvic region with two metallic femoral prosthesis and a cylindrical insert in the prostate region for gel dosimetry was developed for applications in 3D dosimetry of prostate IMRT treatments, using a MAGIC-f gel dosimeter. The procedures for gel dosimetry were all evaluated in the cylindrical insert to test the gel's response in this geometry.