Measurement of dose distribution from treatment of shallow brain tumors in BNCT by NIPAM polymer gel

Because of the unique characteristics of polymer gel dosimeters, it appears that these gels might offer a reliable method for measuring absorbed radiation dose from various radiotherapy techniques, such as BNCT. In this study, the ability of NIPAM polymer gel to record the dose distribution from the BNCT treatment modality was evaluated by simulating the clinical conditions for treatment of shallow tumors. In this regards, two polymethyl methacrylate (PMMA) cylinder phantoms, measuring 8 cm in diameter and 6 cm in height with a wall thickness of 5 mm, were used for irradiating the gel in front of the BNCT beam of the Tehran Research Reactor (TRR). One of the phantoms was filled by only NIPAM gel prepared by standard formulation and the other one containing about 20 cc NIPAM gel with 30 ppm of 10B which was embedded inside the standard gel, with no separating layer, at a depth of 1 cm from the phantom wall. From the results, 18% increased dose was recorded in the area that was loaded the 10B doped gel in comparison with the pure NIPAM gel. It can be concluded that NIPAM gel has the potential to be used in verification of BNCT treatment planning.