background: the assessment of rbe quantity in the treatment of cancer tumors with proton beams in treatment planning systems (tps) is of high significance. given the significance of the issue and the studies conducted in the literature, this quantity is fixed and is taken as equal to 1.1. objective: the main objective of this study was to assess rbe quantity of proton beams and their variations...

introduction intensity-modulated radiotherapy (imrt) is becoming an increasingly routine treatment method. imrt can be delivered by use of conventional multileaf collimators (mlcs) and/or physical compensators. one of the most important factors in selecting an appropriate imrt technique is integral dose. integral dose is equal to the mean energy deposited in the total irradiated volume of the p...

Introduction: The dose in computed tomography (CT) often approach or exceed the optimum levels, thereby increasing the probability of cancer induction. With wide application of this diagnostic test, it is expedient to determine the effective dose (ED) for each patient to estimate their cancer risk. This study was conducted to investigate the patient-specific dose (PSD) and cancer risk in CT exa...

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...

osteopenia of prematurity (oop) is a preventable disease. improved survival of premature newborns is associated with an increased incidence of oop. the purpose of this study was to compare the prophylactic effects of two low doses of vitamin d (200 and 400 iu/day) on the clinical, biochemical and radiological indices of the rickets of prematurity. in a randomized clinical trial, 60 preterm newb...

background: radiology staff needs to justify the radiation exposures in order to protect themselves and others from radiation risks. the aims of this study were to examine the awareness level of radiation dose and protection amongst radiographers and to compare their performance between major jordanian hospitals. materials and methods: a cross-sectional survey was conducted in 4 major jordanian...

background: the natural radionuclides are always present in soil and care needs to be taken to minimize the radiation dose to humans. these radionuclides are mostly gamma ray emitting radionuclides which contribute to the radiation dose in long term behavior of radionuclides in soil. health hazards associated with natural radioactivity are of great concern and it is necessary to assess risk due...

background:  this study presents patient specific and organ dose estimation in computed tomography (ct) imaging of thorax directly from patient ct image using monte carlo simulation.  patient's ct image is considered as the patient specific phantom and the best representative of patient physical index in order to calculate specific organ dose. materials and methods: egsnrc /beamnrc monte c...

objective: acute inflammatory demyelinating peripheral neuropathy (guillain-barre-syndrome) is by far the most common cause of immune-medicated peripheral nervous system disease in children; with the near disappearance of poliomyelitis, gbs is responsible for the great majority of cases of acute flaccid paralysis. so far, in several controlled studies, corticosteroids, plasmapheresis and ivig h...

background: x-ray computed tomography (ct) examinations deliver a significant amount of radiation doses to patients comparing to conventional radiography examinations. the objective of the current study was to analyze and investigate the average patient received dose from axial and spiral ct exams in a medical imaging center. material and methods: in this study, the patient imaging technique, w...