background: over recent decades, modern protocols of external beam radio¬therapy and radiation techniques such as intensity-modulated radiotherapy (imrt) have been developed. these methods are extremely sensitive to errors in treatment delivery, so that it is essential to apply a high resolution 3d dosimetry system that has high sensitivity and is capable of measuring and verifying the complex ...

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 aim of this work was to establish how well gel dosimeters performed, as substitutes for brain tissue compared with standard phantom materials such as water, polymethyl-methacrylate (or pmma), a150 plastic and te- liquid phantom material for dosimetry of neutron beams in boron neutron capture therapy. materials and methods: thermal neutron fluence, photon dose and epithermal neut...

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...

Since the introduction of volumetric chemical dosimetry with Fricke gel dosimeters in the 1980s, three-dimensional (3D) dosimetry has been a promising technique for the clinic, since it provides a unique methodology for 3D dose measurement of the complex conformal dose distributions achieved by modern techniques such as Intensity Modulated and Volumetric Arc Radiation Therapy. In the last decad...

Radiation dosimetry by Fricke gel was largely used, generally focused and optimized for radiotherapy applications therefore involving relative high dose levels. Fricke gel dosimetry has several advantages, like dose rate and LET almost independence, 3D mapping, among other. This work presents a novel Fricke gel dosimeter optimized for low dose levels. Several chemical composition were studied v...

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...

Spectrophotometric measurements of the Fricke–gelatin–xylenol orange (FGX) gel dosimeter demonstrated reproducible linear dose response up to 25Gy. However, oxidation processes continue post-irradiation, affecting the response of this dosimetry system. Additional oxygenation during preparation increases the sensitivity of the gel but does not improve the auto-oxidation stability of the dosimete...