Introduction: The present study aimed to generate intensity-modulated beams with Aluminium compensating filters for a conventional telecobalt machine based on the outputs of a treatment planning system (TPS) performing forward planning and cannot simulate directly the compensating filter. Materials and Methods: In order to achieve the beam intensity modulation during treatment planning with th...

Background: Craniospinal radiotherapy faces technical challenges which are due to the sensitivity of the location in which the gross tumor is, and to organs at risk around planning target volume. Using modern treatment planning systems causes a reduction in the complexities of the treatment techniques. The most effective method to assess the dosimetric accuracy and the validity of the ...

background: the purpose of this study was to evaluate nodal irradiation with conventional three-field's technique. materials and methods: fifty patients with breast cancer were enrolled in this study. computed tomography scans in the supine treatment position were imported into a treatment planning system. levels i-iii axillary and supraclavicular nodes were identified and their depths to ...

background: use of contrast agents (cas) during ct simulation for treatment planing system leads to changes in  electron density. in this study we aimed to investigate the effect on  calculated dose of various concentrations of cas on treatment planing systems in different dose calculation algorithms. materials and methods: contrast agent (0.769 mg/ml iopromid) - water mixtures at concentration...

background: the electron contamination may reduce or even diminish the skin sparing property of the megavoltage beam. the detailed characteristics of contaminant electrons are presented for different field sizes and cases. materials and methods: the monte carlo code, mcnpx, has been used to simulate 18 mv photon beam from a varian linac-2300 accelerator. all dose measurements were carried out u...

Equivalent dose from neutrons produced during proton radiotherapy increases the predicted risk of radiogenic late effects. However, out-of-field neutron dose is not taken into account by commercial proton radiotherapy treatment planning systems. The purpose of this study was to demonstrate the feasibility of implementing an analytical model to calculate leakage neutron equivalent dose in a trea...

Background: Understanding of the incident electron energy and angular distributions from clinical electron accelerators (linacs) is important for dosimetry and treatment planning. The most important goals of this study were to evaluate the energy fluence and angular distributions of electron beams from a Neptun 10PC linac using the Monte Carlo (MC) code. Materials and Methods: The lina...