Introduction: To investigate the effects of breathing cycle and tree diaphragm motions on prostate cancer tumors standard uptake value (SUV) during positron emission tomography (PET) and to correct it. Materials and methods: Respiratory motion traces were simulated on the common patient breathing cycle and tree diaphragm motio...

Background: The aim of this study was to develop and implement a Monte Carlo framework for evaluation of patient specific out-of-field organ equivalent dose (OED). Materials and Methods: Dose calculations were performed using a Monte Carlo-based model of Oncor linac and tomographic phantoms. Monte Carlo simulations were performed using EGSnrc user codes. Dose measurements were performed using r...

background: inclusion of inhomogeneity corrections in intensity modulated small fields always makes conformal irradiation of lung tumor very complicated in accurate dose delivery. objective: in the present study, the performance of five algorithms via monte carlo, pencil beam, convolution, fast superposition and superposition were evaluated in lung cancer intensity modulated radiotherapy planni...

background : limited studies are available on the calculation of radiation exposure and its associated risks for people in contact with patients who have been treated with permanent prostate brachytherapy. in this study the changes in the radiation exposure were calculated in different stages of the bladder fullness in prostate seed brachytherapy. methods :magnetic resonance images of three pat...

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×...

i131 is a famous radio-iodine isotope in use for diagnosis and treatment of hyper functioning and cancerous thyroid gland. it is a nuclear reactor product; however nuclear reactor may be unavailable in some areas. replacement by i-124 may be possible, another iodine isotope producible by cyclotron; a system more available than reactor. here absorbed fraction of gamma and beta rays of i-124 thro...

Recent evidences demonstrated that endothelial-to-mesenchymal transition (EndMT) has a crucial role in cancer and is recognized as a unique source of cancer-associated fibroblasts (CAFs). Primo vascular system (PVS) is a new circulatory system which may play an important role in cancer metastasis and regeneration. In the current study, we applied previously established time-saving method to ide...

background: gel polymers are considered as new dosimeters for determining radiotherapy dose distribution in three dimensions. objective: the ability of a new formulation of magic-f polymer gel was assessed by experimental measurement and monte carlo (mc) method for studying the effect of gold nanoparticles (gnps) in prostate dose distributions under the internal ir-192 and external 18mv radioth...