introduction:  skin  sparing  is  one  of  the  most  desirable  characteristics  of  high  energy  photon  beams. however, the photons emerging from the target of linacs are contaminated by secondary  electrons  as  a  result  of  their  interactions  with  air,  collimators,  flattening  filter  and  any  other  objects in their path. this phenomenon tends to increase the skin dose received b...

introduction: the aim of present study was to estimate effective dose from most common procedures performed in nuclear medicine departments of golestan province. methods: data of nuclear medicine procedures performed in 2 nuclear medicine departments in golestan province were collected during 4 years. effective dose, collective effective dose and effective dose per examination were calculated u...

TRiP98, a treatment planning program, was used in the pilot project of heavy ion radiotherapy with scanned ion beams at GSI [1]. Over 400 patients were treated from 1997 to 2008 [2]. Currently TRiP98 is used for research purposes. One big part of the actual research is to make TRiP98 able to handle 4D data sets [3]. This is needed for the treatment of moving tumors (like lung tumors). Due to th...

Monte Carlo codes are utilized for accurate dose calculations in proton radiation therapy research. While they are superior in accuracy to commonly used analytical dose calculations, they require significantly longer computation times. The aim of this work is to characterize a Monte Carlo track-repeating algorithm to increase computation speed without compromising dosimetric accuracy. The track...

Aim of the study Our objective was to quantify the accuracy of dose calculation in the build-up region of the tangential field of the breast for a TiGRT treatment planning system (TPS). Material and methods Thermoluminescent dosimeter (TLD) chips were arranged in a RANDO phantom for the dose measurement. TiGRT TPS was also used for the dose calculation. Finally, confidence limit values were o...

Log file-based methods are attracting increasing interest owing to their ability to validate volumetric-modulated arc therapy outputs with high resolution in the leaf and gantry positions and in delivered dose. Cross-validation of these methods for comparison with measurement-based methods using the ionization chamber/ArcCHECK-3DVH software (version 3.2.0) under the same conditions of treatment...

UNLABELLED The development of advanced radiation treatment techniques such as intensity modulated radiation therapy (IMRT) and volumetric intensity modulated arc therapy (VMAT) require more accurate dose calculation algorithms within the treatment planning systems (TPS) considering that the human body is composed of tissues of widely differing radiological properties and the characteristics of ...

background: in vivo dosimetry is a method for estimation of overall error in the delivered dose to the patients at the end of radiotherapy process. in this research, two methods for target dose calculation were evaluated on midline and central axis of photon beams in in vivo dosimetry of thorax fields. materials and methods: entrance and exit doses for anterior and lateral fields of thorax were...