Use of Gel Dosimetry to Characterise the Dose Distribution in the Spheroidal Holder for Liver Treatment at the HFR Petten

The preparation of the treatment of the human liver tumour starts from the evaluation of the dosimetry of the problem. Simulations with a simplified spheroidal model of the human liver and the definition of the neutron beam normally used for BNCT clinical trials in Petten have been performed. The choice and the main properties of this liver facility is explained in another contribution to this conference. In order to validate the design calculations, which were performed using the Monte Carlo code MCNP, both activation foils and gel dosimeters have been used. The gel dosimeter is a technique to obtain continuous images of absorbed dose. By properly designing the gel isotopic composition, it is possible to separate the gamma dose and the dose due to charged particles, such as those produced in 10B reactions, and consequently the thermal neutron flux can be deduced. Therefore, this method gives an indication of the thermal neutron flux and the doses along pre-defined axes in the plane of the gel dosimeters, which have been positioned in the liver holder and surrounded with water. The calculated thermal neutron flux appears to be consistent with that obtained in strategic places of the liver holder, making use of the activation foils. The gamma and boron dose mappings obtained by the gel dosimeters confirm that the BNCT liver facility in Petten is able to provide a proper homogeneous thermal neutron distribution in the liver, as required for the successful treatment of the liver metastases.

NIEVAART Victor Alexander;  CARRARA Mauro;  VANOSSI Elena;  DAQUINO Giuseppe Giovanni; 

GAMBARINI Grazia; 

2007-01-16

International Society for Neutron Capture Therapy (ISNCT)

JRC33100

https://publications.jrc.ec.europa.eu/repository/handle/JRC33100,