Background: Accurate dose calculations in small beamlets and lung material have been a great challenge for most of treatment planning systems (TPS).  In the current study, the dose calculation accuracy of TiGRT TPS was evaluated for small beamlets in water and lung phantom by comparison to Monte Carlo (MC) calculations. Materials and Methods: The head of Siemens Oncor-impression linac...

introduction the use of cut-outs in electron applicators make changes on output, isodose, and percentage depth dose (pdd) curves. these changes and electron beam dose distribution in the form of three-dimensional (3d) can be measured by gel dosimeters. materials and methods dosimetry was performed with and without a square shield (6×6 cm2 field). the energies were 4, 9, and 16 mev and phantom w...

In accurate radiotherapy, energy spectra of high energy x-ray greatly affect the accuracy of dose calculation. Conventional discrete method failed to realize the stable solution, and the Schiff formula could not reflect the practical geometric shape of different linac system that showed the limitation to apply to other linacs. To obtain the photon energy spectra of linac in radiotherapy effecti...

The International Atomic Energy Agency Technical Reports Series-398 code of practice for dosimetry recommends measuring photon percentage depth dose (PDD) curves with parallel-plate chambers. This code of practice was published before flattening filter-free (FFF) beams were widely used in clinical linear accelerators. The choice of detector for PDD measurements needs to be reassessed for FFF be...

A T-shaped fiber-optic phantom-dosimeter system was developed using square scintillating optical fibers, a lens system, and a CMOS image camera. Images of scintillating light were used to simultaneously measure the transverse and longitudinal distributions of absorbed dose of a 6 MV photon beam with field sizes of 1 × 1 and 3 × 3 cm(2). Each optical fiber has a very small sensitive volume and t...

Background: Radiation-sensitive polymer gels are among the most promising three-dimensional dose verification tools and tissue-like phantom developed to date.Objective: The aim of this study is an investigating of percentage depth dose enhancement within the gel medium with used of conformal distribution gold nanoparticle as contrast agents by high atomic number material.Methods: In this work t...