Journal of the Korean Society of Radiology (한국방사선학회논문지)

The Korean Society of Radiology (한국방사선학회)
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Characteristics of Scattered Rays Depending on the Use of a Flattening Filter

선속평탄 여과판 사용 유무에 따른 산란선 특성

  • Jin, SeongJin (Department of Radiation Oncology, Haeundae Paik Hospital) ;
  • Park, ChulWoo (Department of Radiological Technology, Dong-Eui Institute of Technology) ;
  • Je, Jaeyong (Department of Radiological Technology, Dong-Eui Institute of Technology)
  • 진성진 (해운대백병원 방사선종양학과) ;
  • 박철우 (동의과학대학교 방사선과) ;
  • 제재용 (동의과학대학교 방사선과)
  • Received : 2016.01.03
  • Accepted : 2016.01.30
  • Published : 2016.01.30
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Abstract

This Study aims at measuring scattered rays depending on the use of a flattening filter when radiation is irradiated using a linear accelerator. measurement of the scattered rays, an ionization chamber was used, and the energy of the irradiated radiation was 6 MV and 10 MV. The ionization chamber was located at the spot 15 cm, 25 cm, 35 cm and 45 cm far away from the center of gantry rotation, and the scattered rays were measured according to whether a flattening filter was used or not and to the distance. As the result of investigation of 100 cGy about each energy, when the flattening filter was not used with 6 MV, it occurred at a low level of 65%, and with 10 MV at that of 55%. In other words, it's been concluded that when a flattening filter is not used for radiation dose of the parts around the critical organ, scattered rays generate in a small quantity, and it's a useful way to decrease the stochastic effect of radiation.

본 연구는 선형가속기를 이용한 방사선 조사에서 선속평탄 여과판 사용 유무에 따른 산란선을 측정하고 자 한다. 산란선 측정은 전리함을 사용하였으며, 조사한 방사선의 에너지는 6 MV와 10 MV 이다. 갠트리 회전 중심에서 전리함을 15, 25, 35, 45 cm 거리에 위치시키고 선속평탄 여과판 사용 유무와 거리에 따른 산란선을 측정하였다. 각각의 에너지에 대하여 100 cGy 조사한 결과 6 MV에서 선속평탄 여과판을 사용하지 않은 것에서 65% 정도로 낮게 발생되었고, 10 MV 에서는 55% 정도로 낮게 발생되었다. 즉, 방사선 치료에서 결정 장기 주변의 선량은 선속평탄 여과판을 사용하지 않을 때 산란선이 적게 발생되어 방사선에 대한 확률적인 영향을 줄이기 위한 유용한 방법으로 판단되어진다.

Keywords

References

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