Introduction: Head scans are the most frequently performed computed tomography (CT) examinations worldwide. However, there is growing concern over the probability of increased cancer risks among the exposed populations. Diagnostic reference levels (DRLs) identify radiation dose that is not commensurate with clinical objectives. The aim of this study was to establish DR...

For reasons of phantom material reproducibility, the absorbed dose protocols of the American Association of Physicists in Medicine (AAPM) (TG-51) and the International Atomic Energy Agency (IAEA) (TRS-398) have made the use of liquid water as a phantom material for reference dosimetry mandatory. In this work we provide a formal framework for the measurement of absorbed dose to water using ioniz...

introduction radiotherapy is regarded as the first treatment of choice for nasopharyngeal carcinoma. despite the advantages of radiotherapy, patients may suffer from a wide range of side-effects due to the presence of many sensitive normal tissues in these regions. if the absorbed dose exceeds the tolerance level in parotid glands and the spinal cord, myelopathy, lhermitte's sign and xeros...

background: the purpose of this study was to find the accurate absorbed dose in the femur bone marrow during the x-ray radiography for constant mas and aec techniques. materials and methods: the dosxyznrc was used to simulate radiation doses in two human femurs during diagnostic radiography. egsnrc phantoms produced from actual ct images of human femurs were modified by adding seven micrometre ...

background: radiotherapy plays an important role in the management of most malignant and many benign primary central nervous system (cns) tumors. radiotherapy affects both tumor cells and uninvolved normal cells; so, it is important to estimate absorbed dose to organs at risk in this kind of treatment. the aim of this study was to determine the absorbed dose to chiasma, lens, optic nerve, retin...

introduction: average glandular dose calculation in mammography with mo-rh target-filter and dose calculation for different situations is accurate and fast. material and methods: in this research, first of all, x-ray spectra of a mo target bombarded by a 28 kev electron beam with and without a rh filter were calculated using the mcnp code. then, we used the sobol-wu parameters to write a fortra...

background: human activities such as mining enhance the radioactivity levels above normal background which can lead to an incremental increase in the radiation risk to the population. materials and methods: 20 tailing enriched soil samples collected around maiganga coal mine, gombe, northeast nigeria were assessed for their 226ra, 232th and 40k contents using hpge gamma-ray detector. results: t...

background: the presence of radionuclides in the soil, measures need to be taken to minimize the radiation dose to humans. it is mostly gamma-emitting radionuclides that contribute to the radiation dose in long term behavior of these radionuclides in soil may determine the extent to which such countermeasures need to be applied. materials and methods: the activity concentration of these radionu...

determination of the total body absorbed dose consists of two parts: beta radiation absorbed dose and gamma radiation absorbed dose. the first part is generally determined by clinical data, while the second part has a parameter called absorbed ratio and is determined by computational methods. the monte-carlo computational methods have been shown to be the most suitable in determination of the a...