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Skin and build up dose determination for a 2.5 MV medical linear accelerator imaging beam

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Abstract

The 2.5 MV Imaging beam produced by a Varian TrueBeam linear accelerator produces a dose build up effect at the beam entrance similar to other high energy photon beams. The surface dose values were found to range from 39% of maximum dose at a 5 cm × 5 cm field size up to 69% of maximum at a 40 cm × 40 cm field. The depth of maximum dose deposition was found to range from 5 mm at smaller field sizes to 4 mm at larger field sizes. Whilst large absorbed doses will not be delivered utilizing these beams, the data provided will allow the medical physics community to assess and estimate doses to patient’s skin and subcutaneous tissue from low energy MV imaging beams.

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Authors and Affiliations

  1. Department of Radiation Oncology, Chris O’Brien Lifehouse, 119 – 143 Missenden Road, Camperdown, NSW, 2050, Australia

    Martin Butson, Johnny Morales & Robin Hill

  2. Institute of Medical Physics, School of Physics, The University of Sydney, Sydney, NSW, 2006, Australia

    Martin Butson, Ethan Butson & Robin Hill

  3. School of Physics, The University of Sydney, Sydney, NSW, 2006, Australia

    Ethan Butson

  4. School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Level 4 O Block, Garden’s Point, QLD, 4001, Australia

    Johnny Morales

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  1. Martin Butson
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  4. Robin Hill
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Correspondence to Martin Butson.

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No procedures involving human participants were performed in this study. No procedures involving animals was performed in this study.

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Butson, M., Butson, E., Morales, J. et al. Skin and build up dose determination for a 2.5 MV medical linear accelerator imaging beam. Australas Phys Eng Sci Med 42, 1177–1181 (2019). https://doi.org/10.1007/s13246-019-00792-z

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  • DOI: https://doi.org/10.1007/s13246-019-00792-z

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