Progress in Medical Physics (한국의학물리학회지:의학물리)

Korean Society of Medical Physics (한국의학물리학회)
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Assessment of Radiation Dose from Radioactive Wedge Filters during High-Energy X-Ray Therapy

  • Back, Geum-mun (Department of Radiation Oncology, Asan Medical Center) ;
  • Park, Sung Ho (Department of Neurosurgery, Ulsan University Hospital) ;
  • Kim, Tae-Hyung (Department of Radiological Science, Kangwon National University)
  • Received : 2017.03.17
  • Accepted : 2017.07.01
  • Published : 2017.06.30
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Abstract

This paper evaluated the amount of radiation generated by wedge filters during radiation therapy using a high-energy linear accelerator, and the dose to the worker during wedge replacement. After 10-MV photon beam was irradiated with wedge filter, the wedge was removed from the linear accelerator, and the dose rate and energy spectrum were measured. The initial measurement was approximately 1 uSv/h, and the radiation level was reduced to 0.3 uSv/h after 6 min. The effective half-life derived from the dose rate measurement was approximately 3.5 min, and the influence of AI-28 was about 53%. From the energy spectrum measurements, a peak of 1,799 keV was measured for AI-28, while the peak for Co-58 was not measured in the control room. The peaks for Au-106 and Cd-105 were found only measurement was done without wedge removement from the linear accelerator. The additional doses received by the radiation worker during wedge replacement were estimated to be 0.08-0.4 mSv per year.

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