Background: Dose calculation algorithms play a very important role in predicting the explicit dose distribution. We evaluated the percent depth dose (PDD), lateral depth dose profile, and surface dose volume histogram in inhomogeneous media using calculation algorithms and inhomogeneity correction methods. Materials and Methods: The homogeneous and inhomogeneous virtual slab phantoms used in th...

BACKGROUND The recently implemented mARC-rotation-technique is capable to deliver high dose rate bursts. For the case of hypopharynx cancer plans we evaluate whether the mARC can achieve an advantage in treatment time in comparison to IMRT. These plans consider two arcs with flat and flattening filter free (FFF) beam energies. MATERIALS AND METHODS For 8 hypopharynx-cancer patients step-and-s...

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...

Electron paramagnetic resonance (EPR) spectroscopy has been successfully employed to determine radiation dose using alanine. The EPR signal intensity reflects the number of stable free radicals produced, and provides a quantitative measurement of the absorbed dose. The aim of the present study was to explore whether this principle can be extended to provide information on spatial dose distribut...

Background: Considering that some vital organs exist in the head and neck region, the treatment of tumors in this area is a crucial task. The existence of air cavities, namely sinuses, disrupt the radiotherapy dose distribution. The study aims to analyze the effect of maxillary, frontal, ethmoid and sphenoid sinuses on radiotherapy dose distribution by Monte Carlo method.Materials and Methods: ...

Introduction: The dosimetric characteristics of patch sources including 32P, 90Y, 188Re and 166Ho, which are employed for radionuclide skin therapy, have been evaluated in current study Materials and Methods: The patch sources understudy were modeled by MCNPX Monte Carlo code and corresponding depth dose distribution, transverse dose profile and isodose curves...

Background: Medical X-rays are the largest man-made source of public exposure to ionizing radiation. While the benefits of Computed Tomography (CT) are well known in accurate diagnosis, those benefits are not risk-free. CT is a device with higher patient dose in comparison with other conventional radiation procedures. Objective: This study is aimed at evaluating radiation dose to patients from ...