Abstract
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 T2 (spin- spin relaxation time) in the irradiated gel dosimeters. Dependence of 1/T2 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.