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: since 1984 mri gel dosimetry has been introduced as a potential technique for 3d dosimetry. most of the studies have measured r1 (1/t1) or r2 (1/t2) properties of the gel depending on the gel type. we have studied image intensity change in the fricke gel by different mri protocols. materials and methods: gel dosimeters contain 0.4 mm ferrous sulphate, 1 mm nacl, 50 mm h2so4 and 1% b...

introduction: the purpose of this work was to study the ability of mri normoxic polymer gel dosimetry for evaluating the dose distribution in hdr brachytherapy of esophagial cancer at imam reza brachytherapy center (mashhad, iran). materials and methods: initially, 2liters of normoxic gel (magic) was fabricated and then poured into 12 calibration test tubes and placed in a perspex walled phanto...

introduction: the pagat polymer gel dosimeter melts at 30 ˚c and even at room temperature during the summer, so it needs to be kept in a cool place such as a refrigerator. to increase the stability of the pagat gel, different amounts of agarose were added to the pagat gel composition and the pagata gel was manufactured. material and methods: the pagata gel vials were irradiated using a co-60 ma...

Background: Since 1984 MRI gel dosimetry has been introduced as a potential technique for 3D dosimetry. Most of the studies have measured R1 (1/T1) or R2 (1/T2) properties of the gel depending on the gel type. We have studied image intensity change in the Fricke gel by different MRI protocols. Materials and Methods: Gel Dosimeters contain 0.4 mM ferrous sulphate, 1 mM NaCl, 50 mM H2SO4 and 1% b...

Introduction: The purpose of this work was to study the ability of MRI normoxic polymer gel dosimetry for evaluating the dose distribution in HDR brachytherapy of esophagial cancer at Imam Reza brachytherapy center (Mashhad, Iran). Materials and Methods: Initially, 2liters of normoxic gel (MAGIC) was fabricated and then poured into 12 calibration test tubes and placed in a perspex walled phanto...

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...

introduction: despite the fact that the clinical implementation of polymer gel dosimetry has been facilitated after the introduction of normoxic gels, there are still complications in its clinical routine use that are under investigation. in the current work, the feasibility of using a normoxic polymer gel dosimeter named magica has been investigated for use in our clinical brachytherapy applic...

Introduction: Computed tomography (CT) has numerous applications in clinical procedures but its main problem is its high radiation dose to the patients compared to other imaging modalities using x-ray. CT delivers approximately high doses to the nearby tissues due to the scattering effect, fan beam (beam divergence) and limited collimator efficiency. The radiation dose from multi-slice scanners...

Introduction: According to the literature, optical coherence tomography (OCT) can be used measure radiation absorbed dose. This study was carried out to design a computed tomography system for the calculation of absorbed dose and optimization of dose delivery in radiotherapy using gel dosimeters. Material and Methods: An advanced charge-coupled device based OCT system was developed in laborator...