Progress in Medical Physics (한국의학물리학회지:의학물리)

Korean Society of Medical Physics (한국의학물리학회)
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On the Use Factor Analysis and Adequacy Evaluation of CyberKnife Shielding Design Using Clinical Data

  • Cho, Yu Ra (Department of CyberKnife Center, Korea Institute of Radiological & Medical Sciences) ;
  • Jung, Haijo (Radiation Safety Office, Korea Institute of Radiological & Medical Sciences) ;
  • Lee, Dong Han (Department of CyberKnife Center, Korea Institute of Radiological & Medical Sciences)
  • Received : 2018.10.26
  • Accepted : 2018.12.18
  • Published : 2018.12.31
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Abstract

Although the current internationally recommended standard for the use factor (U) applied to CyberKnife is 0.05 (5%), the CyberKnife shielding standard is applied more stringently. This study, based on clinical data, was aimed at examining the appropriateness of existing shielding guidelines. Sixty patients treated with G4 CyberKnife were selected. The patients were divided into two groups, according to whether they underwent skull or spine tracking. Based on the results, the use factors for each wall ranged from 0.028 (2.8%) to 0.031 (3.1%) for the intracranial treatment and 0.020 (2.0%) to 0.022 (2.2%) for the body treatment. Excessive barrier thickness resulted in inefficient use of space and higher cost to the institutions. Furthermore, because the use factor is influenced by the position of the robot, the use factor determined based on the clinical data of this study would facilitate more reasonable treatment room design.

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