Response and toxicity prediction is essential to rational implementation of cancer therapy. The biologic effects of radionuclide therapy are mediated via a well-defined physical quantity, the absorbed dose, which is defined as the energy absorbed per unit mass of tissue. The concepts, basic definitions, and different approaches to the clinical implementation of absorbed dose estimation are revi...

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...

introduction in order to treat uveal melanoma , first, radioactive seeds are laid on a silicone- made substance which is called silastic after that they are inserted in the plaque, and finally, this plaque containing silicone-made substance is stitched to the sclera surface. the dose gradient within the tumor and healthy tissues can be varied due to changing the silastic thickness between scler...

Introduction: In brachytherapy treatments, high-dose sources are used in interstitial placement. In this paper, the modeling of a common breast cancer treatment applicator called MammoSite is done by the Monte Carlo simulation code. Then, to study and calculate the amount of doses in the breast and the dose rate of the organs at risk of radiation, including: lungs, ribs and ski...

introduction: one of the sources of natural occurring radiation was soils. the purpose of article was to determine soil pollution by radiation absorbed dose rate, radium equivalent activity, external hazard index, annual gonad dose equivalent and annual effective dose equivalent. methods & materials: the soil samples was located in chahbahar city in blouchestan of iran, was chosen for studying ...

Absorbed dose rate measurements of a 50 kV(p) handheld X-ray probe source in a water phantom are described. The X-ray generator is capable of currents of up to 40 microA, and is designed for cranial brachytherapy and intraoperative applications with applicators. The measurements were performed in a computer-controlled water phantom in which both the source and the detectors are mounted. Two dif...