Characteristics of Dose Distribution at Junctional Area Using the Divergency Cutout Block in the Abutted Field of Photon and Electron Beams

광자선과 전자선의 인접조사에서 선속 퍼짐현상이 고려된 전자선 차폐물을 이용한 접합 조사면의 선량분포 특성

  • Im, In-Chul (Department of Radiological Science, Dongeui University) ;
  • Lee, Jae-Seung (Department of Radiation Oncology, Good Samaritan Hospital)
  • 임인철 (동의대학교 방사선학과) ;
  • 이재승 (선린의료원 방사선종양학과)
  • Received : 2011.08.05
  • Accepted : 2011.08.23
  • Published : 2011.09.30


This study investigated characteristics of dose distribution at junction field of X-ray and electron beams according to the method for fabricating the insert block on the electron cone. Insert block were fabricated to the divergency cutout block and the straight cutout block. For the 6 MV X-ray and 10 MeV nominal energy of electron beam, we was adjacent to the light field of X-ray and electron beam at a surface of matrix chamber and measured to beam profile of abutted field in the 0, 1, 2, 3 cm measurement depth. As a result, characteristics of dose distribution at junction field, straight block was existent that over dose area exceed the give dose more than 5% and under dose area with a rapid change in dose distribution. However, divergency block had remarkably decreased the over dose area caused by the lateral scattering effects of decrease, and being existed uniformity dose distribution in the junction field. Therefore, divergency block were the benefits of radiation dose delivery, in order to applied the clinical, measurement of electron beams according to the fabrication method of the block should be considered carefully.


Supported by : 동의대학교


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