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Polymer gel dosimeter have been developed as means of detecting and verifying an absorbed doses given to cancer patients for radiotherapy in the range (0-10Gy) as measured and verification dose distributions of three-dimensional (3D) treatments. This article reports on the dosimeter of a new N-isopropanol acrylamide NIPAM, high weight percent T%, %C the mass percent of all comonomer polymer gel formulation (6T%, 20C%), optimized for magnetic resonance imaging (MRI). The aim to investigated MR-based polymer gel dosimeter as a three-dimensional 3D dosimeter in IMRT. Magnetic resonance spin-spin relaxation rate images were acquired and, after calibration, converted to absorbed dose distribution. The dose maps were compared with the dose distribution calculated using ion chamber in one plan and radiographic film for two plans. The dosimeters were irradiated by 4, and 10MV photons for doses in the range (4-10) Gy. The multiecho sequence was used for the evaluation of T 2 (spin-spin relaxation times) in the irradiated gel dosimeters. (%dd) percentage depth dose for (IMRT) intensity modulated radiation therapy / polymer gel & Magnetic resonance imaging = 5.7% at 5cm, other the average dose are 10.45 for dose profile, where %dd percentage depth dose for (IMRT) intensity modulated radiation therapy /ionization chamber and radiographic film(IC&RF) = 4.6% at 5cm other the average dose are 10.45 for dose profile. DVH dose volume histogram for polymer gel & magnetic resonance imaging = 94%, but DVH dose volume histogram for point by point ionization chamber and radiographic film = 86%.which lessince timing for protocol of integral part of verification radiation therapy.

Polymer gel dosimeter have been developed as means of detecting and verifying an absorbed dose given to cancer patients during radiotherapy in the range of centigrey up to 10 Grey as measured and verifying dose distributions of three-dimensional (3D) treatments. This article reports the dosimetric properties of a new N-isopropanol acrylamide (NIPAM), high weight percent T% ,%C was the mass percent of all co-monomer polymer gel formulation (20T%, 25C%), optimized for magnetic resonance imaging (MRI). In addition, the dosimetric properties include: dose response and sensitivity, energy & LET, temperature effects, gel pH, gel aging and stability, magnetic field strength, dose rate dependence. This study concentrated on assessment of the basic dosimeter properties of a polymer gel evaluated by MRI. The dosimeters were irradiated by 6 and 10MV photons for doses in the range (4-10) Gy. The multi-echo sequence was used for the evaluation of T 2 (spin-spin relaxation time) in the irradiated gel dosimeters. Dependence of 1/T 2 on the above factors was studied, The purpose of this work was to evaluate the (NIPAM) as monomer N,N'-methylene bis acrylamide a high level dissolved crosslinker where it is a neurotoxin.There is found that no significant dose rate effects in polymer gels were observed using evaluation, although dose response depends on the temperature at which the dosimeter is evaluated. The strength of the magnetic field during evaluation may also influence the dose response. So it is recommended that the gel formulation be imaged between 15-36 h after irradiation.

This study describes the preparation method of alumina (Al 2 O 3 ) as a type of thermoluminescence dosimeter (TLD) to monitor gamma photons (γ-rays) in abroad band of radioactive doses (0.5 : 2000 Gy). Alumina is selected in this study because it has a relatively low cost TL material and can be easily prepared. Aluminum oxide (Al 2 O 3 ) was chemically prepared using two different methods which are the Sol-Gel and Co-precipitation methods. For each method, the produced alumina (Al 2 O 3 ) was divided into 4 groups which was thermally treated at (400, 600, 800, 1100°C) respectively for 6 hours for each group. The crystalline features, morphology and sample composition of the prepared samples were chemically characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX). Al 2 O 3 prepared by the Coprecipitation method which was treated at 1100°C (P4) was found to exhibit the highest gamma ray response compared to other samples. The deconvolution analysis showed that the main TL glow curve consisted of ( 5) overlapped peaks corresponding to number of traps. The linearity of the gamma response for this sample appeared in doses ranging from 1 Gy up to 200 Gy. The minimum detectable dose that can be detected by precipitated-alumina sample (P1) was calculated mathematically to be 3.653 mGy. The fading was found to be 45.6 % after being stored for 45 days at room temperature and approximately 65 % after 90 days. This sample was reproducible according to the repeated TL results for the same sample for 5 times as their values were very close from one other with standard deviation (� σ) 0.96 %. Henceforth, Co-precipitated αalumina can be used as a TL-Micro dosimeter.