Electronic portal imaging devices (EPIDs) have been the preferred tools for verification of patient positioning for radiotherapy in recent decades. Since EPID images contain dose information, many groups have investigated their use for radiotherapy dose measurement. With the introduction of the amorphous-silicon EPIDs, the interest in EPID dosimetry has been accelerated because of the favourabl...

This study presents a 3D dose mapping of complex dose distributions using an x-ray computed tomography (CT) polymer gel dosimetry technique. Two polyacrylamide gels (PAGs) of identical composition were irradiated with the same four arc stereotactic treatment to maximum doses of 15 Gy (PAG1) and 8 Gy (PAG2). The PAGs were CT imaged using a previously defined protocol that involves image averagin...

Advanced radiation techniques such as intensity-modulated radiotherapy (IMRT) for complex geometries in which targets are close to organs at risk have been introduced in radiation therapy, creating a need for procedures that allow easy three-dimensional (3-D) measurement of dose for verification purposes. Polymer gels that change their material properties when irradiated have been suggested for...

Introduction The use of cut-outs in electron applicators make changes on output, isodose, and percentage depth dose (PDD) curves. These changes and electron beam dose distribution in the form of three-dimensional (3D) can be measured by gel dosimeters. Materials and Methods Dosimetry was performed with and without a square shield (6×6 cm2 field). The energies were 4, 9, and 16 MeV and phantom w...

Introduction: The use of electronic portal imaging devices (EPIDs) is a method for the dosimetric verification of radiotherapy plans both pretreatment and in-vivo. The aim of this study was to test a 2D EPID-based dosimetry algorithm for dose verification of some plans inside a homogenous and anthropomorphic phantom and in-vivo, as well. Materials and Methods: </strong...

Monte Carlo water-equivalence study of two PRESAGE® formulations for proton beam dosimetry T Gorjiara, Z Kuncic, J Adamovics and C Baldock 2013 J. Phys.: Conf. Ser. 444 012090 PRESAGE® is a radiochromic solid dosimeter which shows promising potential for 3D proton beam dosimetry. Since an idea dosimeter should be water-equivalent, total depth dose distributions in two PRESAGE® formulations irra...

background:  in this study a series of basic dosimetric properties of a low-density (ld) gel dosimeter are investigated. the dose response is studied regarding to linearity, sensitivity, dose-rate and energy dependence as well as lung tissue equivalence. materials and methods: the ld gel was made by mixing the polymer gel with expanded polystyrene spheres. energy dependence was studied at two d...

The potential of the PRESAGE™/Optical-CT system as a comprehensive 3D dosimetry tool has been demonstrated. The current study focused on detailed characterization of robustness (intra-dosimeter uniformity and temporal stability) and reproducibility (inter-dosimeter reproducibility) of PRESAGE™ inserts compatible with the RPC H&N phantom. In addition, the accuracy and precision of PRESAGE dose m...