background: monte carlo (mc) modeling of a linear accelerator is a prerequisite for monte carlo dose calculations in external beam radiotherapy. in this study, a simple and efficient model was developed for elekta sl-25 linear accelerator using mcnp4c monte carlo code materials and methods: the head of elekta sl-25 linac was simulated for 6 and 18 mv photon beams using mcnp4c mc code. energy sp...

objective: the passage of ionizing radiation in living cells creates clusters of damaged nucleotides in dna. in this study, dna strand breaks induced by the beta particle of iodine-131 (i-131), have been determined experimentally and compared to monte carlo simulation results as a theoretical method of determining131i damage. materials and methods: in this experimental study, in order to create...

Introduction: There are many ways to treat cancer and pain relief. One of the methods is radiopharmaceutical therapy. Indium 111-rituximab contains the radioisotope indium-111 and rituximab. The Indium-111, after decay, emits gamma rays with energies of 245 KeV and 171 KeV, and beta-radiation of 26 KeV. In this study, the absorbed dose of 111In-Rituximab in human body was calcu...

gamma knife is a new noninvasive method for treatment of patient with brain tumors. ‎another name of this procedure is steriotatic radiosurgery.‎‏ ‏this computerized advanced ‎technique was implicated by a team including neurosurgeon, neuroradialogist, oncologist, and ‎a nurse. this method is used for treatment of certain brain tumors and lesions. the benefits are ‎low risk of postoperative com...

Background: Iodine brachytherapy sources with low photon energies have been widely used in treating cancerous tumors. Dosimetric parameters of brachytherapy sources should be determined according to AAPM TG-43U1 recommendations before clinical use. Monte Carlo codes are reliable tools in calculation of these parameters for brachytherapy sources. Materials and Methods: Dosimetric param...

introduction: image quality and accuracy of in vivo activity quantification in spect are affected by collimator penetration and scatter components, especially in high energy imaging. these phenomena highly depend on the collimator characteristic and photon energy. the presence of penetrated and scattered photons from collimator in spect images degrades spatial resolution, contrast and image qua...