PARaDIM; A PHITS-based Monte Carlo tool for internal dosimetry with tetrahedral mesh computational phantoms

Carter, L. M.*; Crawford, T. M.*; Sato, Tatsuhiko; Furuta, Takuya; Choi, C.*; Kim, C. H.*; Brown, J. L.*; Bolch, W. E.*; Zanzonico, P. B.*; Lewis, J. S.*

Journal of Nuclear Medicine, 60(12), p.1802 - 1811, 2019/12

https://doi.org/10.2967/jnumed.119.229013

Voxel human phantoms have been used for internal dose assessment. More anatomically accurate representation become possible for skins or layer tissues owing to recent developments of advanced polygonal mesh-type phantoms and thus internal dose assessment using those advanced phantoms are desired. However, the Monte Carlo transport calculation by implementing those phantoms require an advanced knowledge for the Monte Carlo transport codes and it is only limited to experts. We therefore developed a tool, PARaDIM, which enables users to conduct internal dose calculation with PHITS easily by themselves. With this tool, a user can select tetrahedral-mesh phantoms, set radionuclides in organs, and execute radiation transport calculation with PHITS. Several test cases of internal dosimetry calculations were presented and usefulness of this tool was demonstrated.

User's manual of a supporting system for treatment planning in boron neutron capture therapy; JAERI computational dosimetry system

Kumada, Hiroaki; Torii, Yoshiya

JAERI-Data/Code 2002-018, 158 Pages, 2002/09

JAERI-Data-Code-2002-018.pdf:30.28MB

A boron neutron capture therapy (BNCT) with epithermal neutron beam is expected to treat effectively for malignant tumor that is located deeply in the brain. It is indispensable to estimate preliminarily the irradiation dose in the brain of a patient in order to perform the epithermal neutron beam BNCT. Thus, the JAERI Computational Dosimetry System (JCDS), which can calculate the dose distributions in the brain, has been developed. JCDS is a software that creates a 3-dimentional head model of a patient by using CT and MRI images and that generates a input data file automaticly for calculation neutron flux and gamma-ray dose distribution in the brain by the Monte Carlo code: MCNP, and that displays the dose distribution on the head model for dosimetry by using the MCNP calculation results. JCDS has any advantages as follows; By treating CT data and MRI data which are medical images, a detail three-dimensional model of patinet's head is able to be made easily. The three-dimensional head image is editable to simulate the state of a head after its surgical processes such as skin flap opening and bone removal for the BNCT with craniotomy that are being performed in Japan. JCDS can provide information for the Patient Setting System to set the patient in an actual irradiation position swiftly and accurately. This report describes basic design and procedure of dosimetry, operation manual, data and library structure for JCDS (ver.1.0)

Radiation dose assessment data for external exposures from radioactive cesium in environment

Takahashi, Fumiaki

no journal, , 

JAEA has developed a radiation transport calculation code PHITS and Japanese adult models that enable us to perform computation dosimetry. In recent years, we have analyzed radiation dose assessment data by PHITS for public external exposure from radioactive cesium following the Fukushima Dai-ichi NPP accident. Here, a numerical method was developed to simulate transport of photons in environment and conversion coefficient data were analyzed to estimate effective dose for public including various ages. An integral dose assessment method was developed to predict radiation dose in future by taking account for cesium transfer and indoor dose reduction data were assessed by PHITS. In addition, the relationship between and effective dose and dosimeter reading was clarified for public exposure. These data were useful to make discussions on returning of habitants and to confirm verification of individual monitoring. These results and future plans on computational dosimetry are to be reported in this presentation.