Effect of skin dose by materials located in treatment field

방사선 치료 시 조사야 내에 위치할 수 있는 이물질이 체표선량에 미치는 영향

  • Hong, Chae-Seon (Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Korea) ;
  • Kim, Kyung-Tae (Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Korea) ;
  • Ju, Sang-Gyu (Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Korea) ;
  • Kim, Jong-Sik (Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Korea) ;
  • Park, Young-Hwan (Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Korea)
  • 홍채선 (성균관의대 삼성서울병원 치료방사선과) ;
  • 김경태 (성균관의대 삼성서울병원 치료방사선과) ;
  • 주상규 (성균관의대 삼성서울병원 치료방사선과) ;
  • 김종식 (성균관의대 삼성서울병원 치료방사선과) ;
  • 박영환 (성균관의대 삼성서울병원 치료방사선과)
  • Published : 2002.12.01

Abstract

Purpose : In radiotherapy, various materials are used to located in treatment field unintentionally. It increases the dose delivered to the skin by interactions of the X-ray within the materials and occurs unwanted skin reaction.(due to the dose build-up effect) This aim of the this study is to measure the increase in skin dose when 13 materials are located in treatment field. Methods : Photon beam measurements were made using an plane-parallel chamber (Markus, PTW-Freiburg) in a polystyrene phantom. skin dose were measured using various overlaying 13 materials. a fixed geometry of a $10{\times}10cm$ field, a SSD=100cm and photon energy 4MV on Varian CLINAC 600C accelerator were used for all measurements. Results : There is an increase in skin dose for all materials($16.4{\sim}160.1\%$). As a percentage of maximum dose, the lowest skin dose were measured for the underwear with silk($43.2\%$) and the highest were measured for the 100m1 fluid-bag($96.6\%$) Conclusion : There is a significant increase in skin dose with 13 materials in the treatment field. a significant increase in skin dose can occur which could produce unwanted skin reaction. considerations for placement of 13 materials to be outside the treatment field whenever possible should be used to keep skin dose to a minimum level.

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