Measurement of ferric ion diffusion coefficient in Fricke-infused agarose gel from MR image intensity changes
نویسندگان
چکیده
Abstract-A mathematical modeling was adopted to calculate the ferric ion diffusion coefficient based on the radiation induced magnetic resonance (MR) image intensity change in Fricke-agarose gels. A fast magnetic resonance imaging acquisition technique was employed to avoid the smearing of acquired data due to diffusion over an extended period of time. Our results showed that for a Fricke-agarose gel contained 1mM ammonium ferrous sulfate, 1% agarose, 1mM sodium chloride and 50mM sulfuric acid, its ferric ion diffusion coefficient is 1.31×10-2cm2h-1 in room temperature. This value falls within the 1 ~ 2×10-2cm2h-1 range obtained by previous studies under varying concentrations of gel ingredients. KeywordsMRIFricke-infused gel dosimetry, ferric ion diffusion, gamma knife radiosurgery
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