introduction: the selection of suitable beam angles and weights in external-beam radiotherapy is at present generally based upon the experience of the planner. therefore, automated selection of beam angles and weights in forward-planned radiotherapy will be beneficial. material and methods: in this work, an efficient method is presented within the matlab environment to investigate how to improv...

introduction:the use of beta emitters is one of the effective methods for palliation of bone metastasis. the risk of normal tissue toxicity should be evaluated in the bone pain palliation treatment. methods: in this study, the monte carlo simulation code mcnpx was used for simulation a bone phantom model consisted of bone marrow, bone and soft tissue. specific absorbed fractions were calculated...

The radial distribution of dose about the path of a heavy ion, principally from delta rays, is one of the central contributions of atomic physics to the systematization of high LET radiation effects in condensed matter, whether the detection arises in chemical, physical, or biological systems. In addition to the radial distribution of dose, we require knowledge of the response of the system to ...

In radiotherapy practice, one often needs to compare two dose distributions. Especially with the wide clinical implementation of intensity-modulated radiation therapy, software tools for quantitative dose (or fluence) distribution comparison are required for patient-specific quality assurance. Dose distribution comparison is not a trivial task since it has to be performed in both dose and spati...

chlorotoxin is a 36 amino acids peptide, which is able to block chloride channels isolated from mouse brain. a derivative of chlorotoxin is synthesized and it is labeled by iodine 131; then animal experiments carry out on rats. multiple organ doses may be calculated with biological distribution results in rats with labeled compounds using simulated mcnp4c code. human dose can be calculated usin...

background: in radiation therapy, the peripheral dose is important when anatomical structures with very low dose tolerances are involved. in this study, the two available calculation algorithms of the varian eclipse 8.6 treatment planning system(tps), the anisotropic analytic algorithm (aaa) and pencil-beam convolution (pbc) was used to compare measured and calculated peripheral dose distributi...

introduction: gafchromic ebt films are one of the self-developing and modern films commercially available for dosimetric verification of treatment planning systems (tpss). their high spatial resolution, low energy dependence and near-tissue equivalence make them suitable for verification of dose distributions in radiation therapy. this study was designed to evaluate the dosimetric parameters of...