introduction: in radiotherapy, methods of treatment planning are becoming increasingly more complicated. this requires verification of the doses delivered to increasingly smaller and more precise regions. radiotherapy techniques are continuously employing smaller and smaller field sizes to deliver tighter radiation doses with higher therapeutic ratios, generating interest among researchers to p...

background: the human body contains of different tissues and cavities with different physical and radiological properties. most important among these are tissues and cavities that are radiologically different from water, including lungs, sinuses and bones. gel dosimetry provides a unique feature to display dose distributions occurring in clinical radiation therapy in three dimensions. materials...

Background: In this work investigation of the normoxic PAGAT polymer gel dosimeter such as sensitivity, the R2-dose response with post time and the percentage depth dose (PDD) of PAGAT polymer gel dosimeter have been undertaken. Materials and Methods: Using MRI, the formulation to give the maximum change in the transverse relaxation rate R2 was determined to be 4.5% N,N'-methylenbis- ...

Introduction: Bismuth-based nanoparticles having high atomic number and electron density, besides of being utilized as CT contrast agent, stand as a strongly proposed method for dose enhancement in radiotherapy. Embedded nanoparticle in polymer gel dosimeter poses the first step to assess the dose enhancement capability in nanoparticles. To this end, MAGICA gel dosimeter, whic...

The use of polymer gels to record radiation dose distributions in three dimensions was first proposed in 1992 as a proof-of-principle [1]. The accuracy of these early polymer gel dosimeters and scanning methods was not sufficient for most clinical applications [2]. Since then, several efforts were made to increase the accuracy and precision of both the physical gel dosimeter and the scanning te...

Many kinds of stimuli-responsive polymer and gels have been developed and applied to biomimetic actuators or artificial muscles. Electroactive polymers that change shape when stimulated electrically seem to be particularly promising. In all cases, however, the mechanical motion is driven by external stimuli, for example, reversing the direction of electric field. On the other hand, many living ...

Introduction: Polymer gel dosimeters contain chemical materials sensitive to the radiation which are polymerized by the radiation as a function of absorbed dose. So information of spatial dose distribution can be extracted by imaging from irradiated gel. Among imaging techniques, computed tomography (CT) poses as an attractive method because of practical advantages such as acce...

Background: Radiation-sensitive polymer gels are among the most promising three-dimensional dose verification tools and tissue-like developed to date. Among the special features of this type of dosimeters, is be doped with other elements or chemicals which made them appropriate for investigating of dose enhancement with contrast agents, by high atomic number. Material and Methods: In this study...

Introduction: In radiotherapy, treatment planning methods are evaluating and transforming every day, so precision in calculation and determination of dose delivery process is performing more important role in radiotherapy than past. In modern radiotherapy treatments, deramatically increase of small fields utilization, causes the polymeric gels has known as the most reliable dos...