title: Computer simulation of a backscattered X-ray fluorescence system.
abstract: An EGSnrc user code is developed to simulate a backscattered geometry in vivo x-ray fluorescence system for the measurement of platinum concentration in head and neck tumours. The user code is fundamentally based on a previous study which used the EGS4 Monte Carlo code. The new user code, which we have developed in this study, has new improvements which made it able to simulate the process of photon transportation through the different components of the modelled x-ray fluorescence system. The simulation process included modelling of the photon source, collimators, phantoms and detector. Simulation results were compared and evaluated against x-ray fluorescence data obtained experimentally from an existing system developed by the Swansea In vivo Analysis and Cancer Research Group. In addition, simulation results of this study were also compared with our previous study in which the EGS4 user code was used. Comparison between results has shown that the new EGSnrc user code was able to reproduce the spectral shape obtained using the experimental x-ray fluorescence system. The area under the Compton peak differs by 2.5% between the experimental measurement and the EGSnrc simulation. Similarly, the area under the two Pt Kα peaks differs by 2.3% and 2.2%.
authors.affiliation: Department of Physics, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia. Tel.: +966 12 5270000; Fax: +966 12 5564560; E-mail: fhghorabie@uqu.edu.sa.
authors.forename: Fayez H H
authors.initials: FH
authors.lastname: Al-Ghorabie
mesh_terms: D000970:Antineoplastic Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D003198:Computer Simulation; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D009010:Monte Carlo Method; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012984:Software; D013052:Spectrometry, X-Ray Emission / Q000379:methods*
chemical_list: D000970:Antineoplastic Agents
keywords: EGS4; EGSnrc; computer simulation; in vivo XRF