background: because of the adverse effects of ionizing radiation on fetuses, prior to radiotherapy of pregnant patients, fetal dose should be estimated. fetal dose has been studied by several authors in different depths in phantoms with various abdomen thicknesses (at). in this study, the effect of maternal at and depth in fetal dosimetry was investigated, using peripheral dose (pd) distributio...

introduction: radioiodine therapy is an effective method for treating thyroid cancer carcinoma, but it has some affects on normal tissues, hence dosimetry of vital organs are important to weigh the risks and benefits of this method. the aim of this study is to measure the absorbed doses of important organs by mcnp (monte carlo n particle) simulation and comparing the results of different method...

background: palladium-103 (103pd) is a brachytherapy source for cancer treatment. the monte carlo codes are usually applied for dose distribution and effect of shieldings. monte carlo calculation of dose distribution in water phantom due to a med3633 103pd source is presented in this work. materials and methods: the dose distribution around the 103pd model med3633 located in the center of 30×30...

background: monte carlo and experimental relative dose determination in a water phantom, due to a high dose rate (hdr) 192ir source is presented for real energy spectrum and monochromatic at 356 kev. materials and methods: the dose distribution has been calculated around the 192ir located in the center of 30 cm ×30 cm ×30 cm water phantom using mcnp4c code by monte carlo method. relative dose v...

introduction: in recent decades, several monte carlo codes have been introduced for research and medical applications. these methods provide both accurate and detailed calculation of particle transport from linear accelerators. the main drawback of monte carlo techniques is the extremely long computing time that is required in order to obtain a dose distribution with good statistical accuracy. ...

background: high-energy linear accelerator (linac) is a valuable tool and the most commonly device for external beam radiation treatments in cancer patients. in the linac head, high-energy photons with energies above the threshold of interaction produce photoneutrons. these photoneutrons deliver the extra dose to the patients in the planning treatment and increase the risk of secondary cancer. ...

background: stereotactic radiosurgery is an important clinical tool for the treatment of small lesions in the brain, including benign conditions, malignant and localized metastatic tumors. a dosimetry study was performed for elekta ‘synergy s ’ as a dedicated stereotactic radiosurgery unit, capable of generating circular radiation fields with diameters of 1-5 cm at isocentre using the beam/egs4...

Background: Monte Carlo and experimental relative dose determination in a water phantom, due to a high dose rate (HDR) 192Ir source is presented for real energy spectrum and monochromatic at 356 keV. Materials and Methods: The dose distribution has been calculated around the 192Ir located in the center of 30 cm ×30 cm ×30 cm water phantom using MCNP4C code by Monte Carlo method. Relati...