There has been much research effort in the development of an accurate and reliable threedimensional dose verification system, prompted by the advances of technologies in radiation treatment of cancer patients. New radiotherapy techniques such as intensity modulated radiation therapy (IMRT), stereotactic radiosurgery (SRS) and high dose rate (HDR) brachytherapy are aimed at dose deliveries that ...

Introduction: The purpose of the current study was to investigate the effect of X-ray spectra on the sensitivity of a polymer gel dosimeter imaged with a conventional computed tomography (CT) scanner. Material and Methods: The whole process of CT imaging of an irradiated polymer gel was simulated by MCNPX Monte Carlo (MC) code. The imaging of polyacrylamide gel was accomplished by means of a co...

Introduction: Three physical conditions caused an external beam designated as a small field. The first is the loss of lateral charged particle equilibrium. The second is the effect of collimators on the primary photon source occlusion. The third condition is the size of the detector which is large compared to the field size. The most obvious perturbation effects in last condit...

This work illustrates a procedure to assess the overall accuracy associated with Gamma Knife treatment planning using plugging. The main role of source plugging or blocking is to create dose falloff in the junction between a target and a critical structure. We report the use of MAGAT gel dosimeter for verification of an experimental treatment plan based on plugging. The polymer gel contained in...

Complex interventional radiology (IR) procedures contribute an increasing percentage of the overall medical radiation exposure of the population making accurate dosimetry a challenge. Magnetic resonance (MR) based polymer gel dosimetry has been widely employed in complex dosimetric problems in radiotherapy. The aim of this paper is to investigate the feasibility of normoxic gel dosimetry in IR....

polymer gel dosimeter is the only accurate three dimensional (3d) dosimeter that can measure the absorbed dose distribution in a perfect 3d setting. gel dosimetry by using optical computed tomography (oct) has been promoted by several researches. in the current study, we designed and constructed a prototype oct system for gel dosimetry. first, the electrical system for optical scanning of the g...