Determination of the correction factors used in Fricke dosimetry for HDR 192Ir sources employing the Monte Carlo method

  • Mariano G. David
    Polytechnic Institute of the Rio de Janeiro State University (IPRJ/UERJ), Rio de Janeiro, Brazil

    Radiological Sciences Department, Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil
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  • Camila Salata
    Corresponding author at: Radiological Sciences Department, Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil.
    Radiological Sciences Department, Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil

    Department of Medical and Research Facilities, National Nuclear Energy Authority (CNEN), Rio de Janeiro, Brazil
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  • Carlos E. de Almeida
    Radiological Sciences Department, Rio de Janeiro State University (UERJ), Rio de Janeiro, Brazil
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Published:April 09, 2021DOI:


      • Fricke dosimetry as primary standard for the determination of absorbed dose to water.
      • Monte Carlo method and the correction factors associated to Fricke dosimetry.
      • Reduced uncertainties associated to the determination of the absorbed dose to water;
      • Determination of absorbed dose to water for 192Ir HDR sources.
      • Absolute radiation dosimetry for HDR brachytherapy.



      Fricke dosimetry has shown great potential in the direct measurement of the absolute absorbed dose for 192Ir sources used in HDR brachytherapy. This work describes the determination of the correction factors necessary to convert the absorbed dose in the Fricke solution to the absorbed dose to water. Methods: The experimental setup for Fricke irradiation using a 192Ir source was simulated. The holder geometry used for the Fricke solution irradiation was modelled for MC simulation, using the PENELOPE. Results: The values of the factors determined for validation purposes demonstrated differences of less than 0.2% when compared to the published values. Four factors were calculated to correct: the differences in the density of the solution (1.0004 ± 0.0004); the perturbations caused by the holder (0.9989 ± 0.0004); the source anisotropy and the water attenuation effects (1.0327 ± 0.0012); and the distance from the center of the detection volume to the source (7.1932 ± 0.0065). Conclusion: Calculated corrections in this work show that the largest correction comes from the inverse squared reduction of the dose due to the point of measurement shift from the reference position of 1 cm. This situation also causes the correction due to volume averaging and attenuation in water to be significant. Future versions of the holder will aim to reduce these effects by having a position of measurement closer to the reference point thus requiring smaller corrections.


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        • Nath R.
        • Anderson L.L.
        • Luxton G.
        • Weaver K.A.
        • Williamson J.F.
        • Meigooni A.S.
        Dosimetry of interstitial brachytherapy sources: recommendations of the AAPM radiation therapy committee task group.
        Med Phys. 1995; 22: 209-234
      1. Rivard MJ, Coursey BM, DeWerd LA, Hanson WF, Huq MS, Ibbott GS, et al. Update of AAPM Task Group No. 43 Report: A revised AAPM protocol for brachytherapy dose calculations. Med Phys 2004;31:633–74. DOI:10.1118/1.1646040.

      2. INTERNATIONAL ATOMIC ENERGY AGENCY, Calibration of Photon and Beta Ray Sources Used in Brachytherapy, IAEA-TECDOC-1274, IAEA, Vienna (2002).

        • Austerlitz C.
        • Mota H.C.
        • Sempau J.
        • Benhabib S.M.
        • Campos D.
        • Allison R.
        • et al.
        Determination of absorbed dose in water at the reference point D (r 0, θ0) for an 192Ir HDR brachytherapy source using a Fricke system.
        Med Phys. 2008; 35: 5360-5365
        • El Gamal I.
        • Cojocaru C.
        • Mainegra-Hing E.
        • McEwen M.
        The Fricke dosimeter as an absorbed dose to water primary standard for Ir-192 brachytherapy.
        Phys Med Biol. 2015; 60: 4481-4495
        • Ochoa R.
        • Gómez F.
        • Ferreira I.H.
        • Gutt F.
        • de Almeida C.E.
        Design of a phantom for the quality control of high dose rate 192Ir source used in brachytherapy.
        Radiother Oncol. 2007; 82: 222-228
        • Franco L.
        • Gavazzi S.
        • Almeidade C.E.
        Determination of the G value for HDR 192Ir sources using ionometric measurements (IAEA-CN--182). International Atomic Energy Agency (IAEA, 2010
        • deAlmeida C.E.
        • Ochoa R.
        • Lima M.C.d.
        • David M.G.
        • Pires E.J.
        • Peixoto J.G.
        • et al.
        A feasibility study of fricke dosimetry as an absorbed dose to water standard for 192Ir HDR sources.
        PLoS One. 2014; 9: e115155
        • Salata C.
        • David M.G.
        • de Almeida C.E.
        • El Gamal I.
        • Cojocaru C.
        • Mainegra-Hing E.
        • et al.
        Validating Fricke dosimetry for the measurement of absorbed dose to water for HDR 192Ir brachytherapy: a comparison between primary standards of the LCR, Brazil, and the NRC, Canada.
        Phys Med Biol. 2018; 63: 085004
        • Mantuano A.
        • de Amorim G.J.
        • David M.G.
        • Rosado P.H.G.
        • Salata C.
        • Magalhães L.A.G.
        • et al.
        Linearity and reproducibility response of Fricke dosimetry for low energy X-Ray beam.
        J. Phys. Conf. Ser. 2018; 975: 012052
      3. Salata C, David M, deAlmeida CE, El Gamal I, Cojocaru C, Mainegra-Hing E, et al. SU-F-19A-02: Comparison of Absorbed Dose to Water Standards for HDR Ir-192 Brachytherapy Between the LCR, Brazil and NRC, Canada. Med Phys 2014;41:388–388. DOI:10.1118/1.4889028.

        • Arango E.M.
        • Pickler A.
        • Mantuano A.
        • Salata C.
        • DeAlmeida C.E.
        Feasibility study of the Fricke chemical dosimeter as an independent dosimetric system for the small animal radiation research platform (SARRP).
        Phys Medica. 2020; 71: 168-175
        • Klassen N.V.
        • Shortt K.R.
        • Seuntjens J.
        • Ross C.K.
        Fricke dosimetry: the difference between G(Fe3+) for 60Co γ-rays and high-energy x-rays.
        Phys Med Biol. 1999; 44: 1609-1624
      4. Olszanski A, Klassen NV, Ross CK, Shortt KR. The IRS Fricke dosimetry system. Institute for National Measurement Standards, National Research Council, PIRS-0815, Ottawa, Ontario. 2002 Aug.

      5. Brandan ME, Fantuzzi E, Gregoire V, Howell RW, Paretzke HG. Report 90. J ICRU 2014;14:NP.2-NP. DOI:10.1093/jicru/ndw043.

        • Ma C.-M.
        • Rogers D.W.O.
        • Shortt K.R.
        • Ross C.K.
        • Nahum A.E.
        • Bielajew A.F.
        Wall-correction and absorbed-dose conversion factors for Fricke dosimetry: Monte Carlo calculations and measurements.
        Med Phys. 1993; 20: 283-292
        • Ma C.-M.
        • Nahum A.E.
        Dose conversion and wall correction factors for Fricke dosimetry in high-energy photon beams: analytical model and Monte Carlo calculations.
        Phys Med Biol. 1993; 38: 93-114
        • Taylor R.E.P.
        • Rogers D.W.O.
        EGSnrc Monte Carlo calculated dosimetry parameters for Ir192 and Yb169 brachytherapy sources.
        Med Phys. 2008; 35: 4933-4944
      6. Borg J, Rogers DW. Monte Carlo calculations of photon spectra in air from 192Ir sources. National Research Council Report PIRS-629r, Ontario, Canada. 1999 Mar:11-2.

        • Borg J.
        • Rogers D.W.O.
        Spectra and air-kerma strength for encapsulated 192Ir sources.
        Med Phys. 1999; 26: 2441-2444
        • Law J.
        • Redpath A.T.
        Measurement of ferric ion concentration in the Fricke dosemeter.
        Phys Med Biol. 1971; 16: 531-532
        • Cottens E.
        • Janssens A.
        • Eggermont G.
        • Jacobs R.
        Absorbed dose calorimetry with a graphite calorimeter, and G-value determinations for the Fricke dose meter in high-energy electron beams.
        in: Int. At. Energy Agency IAEA., Vienna, Austria. 1981: 189-211
        • Melhus C.S.
        • Rivard M.J.
        Approaches to calculating AAPM TG-43 brachytherapy dosimetry parameters for 137Cs, 125I, 192Ir, 103Pd, and 169Yb sources.
        Med Phys. 2006; 33: 1729-1737
        • Fernández-Varea JM Salvat F.
        • Sempau J.
        PENELOPE- A Code System for Monte Carlo Simulation of Electron and Photon Transport. InWorkshop proceedings 2008 Jul. Universitat de Barcelona, 2008
        • Badal A.
        • Sempau J.
        A package of Linux scripts for the parallelization of Monte Carlo simulations.
        Comput Phys Commun. 2006; 175: 440-450
        • Watanabe Y.
        • Mizukami S.
        • Eguchi K.
        • Maeyama T.
        • Hayashi S.-I.
        • Muraishi H.
        • et al.
        Dose distribution verification in high-dose-rate brachytherapy using a highly sensitive normoxic N-vinylpyrrolidone polymer gel dosimeter.
        Phys Medica. 2019; 57: 72-79
        • Poder J.
        • Cutajar D.
        • Guatelli S.
        • Petasecca M.
        • Howie A.
        • Bucci J.
        • et al.
        A Monte Carlo study on the feasibility of real-time in vivo source tracking during ultrasound based HDR prostate brachytherapy treatments.
        Phys Medica. 2019; 59: 30-36
        • Pappas E.P.
        • Peppa V.
        • Hourdakis C.J.
        • Karaiskos P.
        • Papagiannis P.
        On the use of a novel Ferrous Xylenol-orange gelatin dosimeter for HDR brachytherapy commissioning and quality assurance testing.
        Phys Medica. 2018; 45: 162-169
        • Peppa V.
        • Pappas E.P.
        • Karaiskos P.
        • Major T.
        • Polgár C.
        • Papagiannis P.
        Dosimetric and radiobiological comparison of TG-43 and Monte Carlo calculations in 192Ir breast brachytherapy applications.
        Phys Medica. 2016; 32: 1245-1251