for superficial lesions, the electrons may be used for radiation therapy. the high energy photons and electrons are produced by a linear accelerator (linac).   many of electron fields need the shielding of normal or critical organs. the electron shields are usually lead slabs with few millimeter thickness which should be placed near the skin, less than 1 centimeter away from skin. in the inspec...

introduction magnetic fields are capable of altering the trajectory of electron beams andcan be used in radiation therapy.theaim of this study was to produce regions with dose enhancement and reduction in the medium. materials and methods the ndfeb permanent magnets were arranged on the electron applicator in several configurations. then, after the passage of the electron beams (9 and 15 mev va...

abstract background: accurate methods of radiation therapy dose calculation. there are different monte carlo codesfor simulation of photons, electrons and the coupled transport of electrons and photons. mcnpis a general purpose monte carlo code that can be used for electron, photon and coupledphoton-electron transport.monte carlo simulation of radiation transport is considered to be one of the ...

conclusions using the maximum dose depth from pdd curves and the inverse square law, the required ssdeff to calculate the dose distribution of the electron beam can be calculated. objectives the aim of this study was to determine the effective source-surface distance (ssdeff) of an electron linear accelerator (linac), and its dependence on energy and depth. materials and methods a varian linac ...

background: for radiotherapy of total skin including sub-cutaneous tissue up to a depth of 3 cm on the entire left leg of an adult (angiosarcoma skin), a complex treatment with multiple stationary electron fields was planned at our clinic. the details of dosimetry, clinical dose measurements are presented. materials and methods: the treatment planned with 6 overlapping 9 mev electron fields in ...

introduction: bacteria and their byproducts are major etiologic factors in endodontic diseases. prevention or reduction of root canal bacterial contamination is the main aim of endodontic treatment. the purpose of this in vitro study was to evaluate the effect of size and taper of master apical file (maf) in reducing bacteria from the apical third of the curved canals using a quantitative scann...

Introduction: Because of importance of impact of the Source to Surface Distance (SSD) in determining of monitor unit for electron-therapy, it is essential to know the Virtual Source Position (VSP) for electron beam for a linear therapeutic accelerator for each energy and field size. , especially using the Khan method (photo distance squared method) And compare the results with...

Background: Cancer is a complex disease with high rate of mortality. At present, Radiation therapy is one of the most common procedures to overcome this situation. The deficiency of conventional method is the lack of fatal dose transmission into the malignant tissue. Hence, uncertain dose may cause regeneration of cancer cells, and relapse of the disease and invasion of the cancer cells to ...