to improve the accuracy of the activity quantification and the image quality in scintigraphy, scatter correction is a vital procedure. the aim of this study is to compare the accuracy in calculation of absorbed dose to patients following bone scan with 99m tc-marked diphosphonates ( 99m tc-mdp) by two different methods of background correction in conjugate view method. this study involved 22 pa...

background: the equivalent dose in the human body due to the natural gamma-emitting radionucides (238u, 232th and 40k) in the surface soil surrounding the consolidated tin mine site in bukuru-jos, nigeria has been determined in this study. materials and methods: measurements of the soil natural radioactivity were made using a multi-channel pulseheight analyzer (canberra series 10 plus) coupled ...

introduction radon is a colorless and tasteless gas which exists in most soils. it is a substance that poses a potential risk for lung cancer in case a person is exposed to high levels over long periods of time. the environmental protection agency (epa) estimates that 90% of lung cancers per year are caused by radon. the aim of this paper is to estimate the absorbed doses of 222rn by mcnpx simu...

background: advances in radiation dosimetry concepts and the development of primary measurement standards based on absorbed dose to water over the last decades offer the possibility to calibrate ionisation chambers directly in terms of absorbed dose to water. the aim of this study is the investigation on utility of artificial body fluid (abf) instead of water by comparing dosimetric measurement...

background: high-velocity carbon ion beams represent the most advanced tool for radiotherapy of deep-seated tumors. currently, the superiority of carbon ion therapy is more prominent on lung cancer or hepatomas. materials and methods: the data for lateral straggling and projected range of monoenergetic 290 mev/u (3.48 gev) carbon ions in muscle tissue were obtained from the stopping and range o...

introduction proton therapy is used to treat malignant tumors such as melanoma inside the eye. proton particles are adjusted according to various parameters such as tumor size and position and patient’s distance from the proton source. the purpose of this study was to assess absorbed doses in eyes and various tumors found in the area of sclera and choroid and the adjacent tissues in radiotherap...

3 PURPOSE: The aim of this study was to investigate how the diagnostic accuracy in digital mammography is affected by dose to the breast. MATERIAL AND METHODS: Structures resembling invasive tumours and microcalcifications on x-ray images were positioned in an anthropomorphic breast phantom equivalent to a 50 mm compressed breast containing 50% glandular tissue. The average glandular dose based...

introduction gallium-67 (67ga) has been used as a radionuclide for imaging a variety of solid tumors since 1969. since then use of various gallium-based radiotracers has been reported. recently, 67ga-labeled acetylacetate bis(thiosemicarbazones) (67ga-aats) complex with significant tumor accumulation and fast blood clearance has been employed. materials and methods in this study, the absorbed d...

A common side effect of radiotherapy used in the treatment of oral cancer is the occurrence of structural and physiological alterations of the salivary glands due to exposure to ionizing radiation, as demonstrated by conditions such as decreased salivary flow. The present study evaluated ultrastructural alterations in the parotid glands of rats receiving a fractionated dose (1,500-cGy) of radia...