abstract   background: the x-ray machines used for radiodiagnosis should meet certain quality assurance (qa) programmes . these are necessary to have good quality radiographs at reasonably low exposure to patients.   materials and methods: dose reduction methods in abdomen x-ray examination were carried out in 10 hospitals in tehran. this paper presents the work, which was implemented on 200 pa...

background: application of dose-area product (dap) quantity has been increased in the clinical practice. dap is relatively easy to measure. dap has been shown to correlate well with the total energy imparted to the patient, which is related to the effective dose. material and methods: in this study, measurements of dap were carried out in a sample of 421 adult patients who underwent conventiona...

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 in this study, effective dose equivalent for the public due to internal exposure to 222radon (222rn) was evaluated in three regions of ramsar, a northern coastal city in iran.                                materials and methods measurements were carried out using a radon monitoring device. outdoor and indoor radon concentrations were measured within 24 hours with an integration in...

introduction in computed tomography (ct) technology, an optimal radiation dose can be achieved via changing radiation parameters such as ma, pitch factor, rotation time and tube voltage (kvp) for diagnostic images. materials and methods in this study, the brain, abdomen, and thorax scaning was performed using toshiba 16-slice scannerand standard aapm and ctdi phantoms. aapm phantom was used for...

introduction relative dose computation is a necessary step in radiation treatment planning. therefore, finding an approach that is both fast and accurate seems to be necessary. the purpose of this work was to investigate the feasibility of natural cubic spline to reconstruct dose maps for linear accelerator radiation treatment fields in comparison with those of the simulation. materials and met...

introduction wedge modifiers are commonly applied in external beam radiotherapy to change the dose distribution corresponding to the body contour and to obtain a uniform dose distribution within the target volume. since the radiation dose delivered to the target must be within ±5% of the prescribed dose, accurate dose calculation by a treatment planning system (tps) is important. the objective ...

the present paper has determined the radioactivity concentrations, which are due to natural occurrence of radionuclides along with heavy metal concentration in water, sediment, and fish from 2 reservoirs in ghana. heavy metal concentrations in all samples were generally within the who safe limits with the average activity concentrations of 238u, 232th, and 40k in water being respectively 0.42±0...

large quantities of radiopharmaceuticals prescribed for treatment and diagnosis are excreted through kidney. therefore, radiation unwanted dose is created in kidney. as a result, exact calculation of prescribed radiopharmaceuticals amount is important. monte carlo method is used for simulation of radiation transport in body due to random nature of radiation. in this research, for the first time...

large quantities of radiopharmaceuticals prescribed for treatment and diagnosis are excreted through kidney. therefore, radiation unwanted dose is created in kidney. as a result, exact calculation of prescribed radiopharmaceuticals amount is important. monte carlo method is used for simulation of radiation transport in body due to random nature of radiation. in this research, for the first time...