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Wedged field using the half-field method with a flattening filter-free photon beam

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Abstract

In this study, we propose a novel wedged field using a half-field flattening filter-free beam without a metallic filter or a moving jaw, and investigate the characteristics of the proposed technique. Dose distributions of the proposed method were first determined in virtual-water or anthropomorphic phantom using a radiotherapy planning system. We evaluated the wedge angle as a function of the field size, collimator rotation, and depth. The wedge angle at 10 MV was observed to be greater than that at 6 MV. The minimum angles at 6 and 10 MV were 17.7° and 40.4°, respectively, while the maximum angles were 33.9° and 48.4°, respectively. We determined that the wedge angle depended on the nominal beam energy and field size, and we verified that the proposed method is capable of delivering a gradient dose distribution and reducing treatment time.

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Authors and Affiliations

  1. Radiation and Proton Therapy Center, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi-cho, Shizuoka, 411-8777, Japan

    Tetsuya Tomida, Masahiro Konno, Tsukasa Yoshida, Kazuaki Yasui & Masahiro Hanmura

  2. Department of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi-cho, Shizuoka, 411-8777, Japan

    Atsushi Urikura

Authors
  1. Tetsuya Tomida
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  2. Masahiro Konno
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  3. Atsushi Urikura
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  4. Tsukasa Yoshida
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  5. Kazuaki Yasui
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  6. Masahiro Hanmura
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Correspondence to Tetsuya Tomida.

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Tomida, T., Konno, M., Urikura, A. et al. Wedged field using the half-field method with a flattening filter-free photon beam. Radiol Phys Technol 13, 201–209 (2020). https://doi.org/10.1007/s12194-020-00561-8

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  • DOI: https://doi.org/10.1007/s12194-020-00561-8

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