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유리선량계를 이용한 투과선량 기반 환자선량 평가 시스템 개발을 위한 가능성 연구

Feasibility Study for Development of Transit Dosimetry Based Patient Dose Verification System Using the Glass Dosimeter

  • 정성훈 (고려대학교 바이오융합공학과) ;
  • 윤명근 (고려대학교 바이오융합공학과) ;
  • 김동욱 (강동경희대학교병원 방사선종양학과) ;
  • 정원규 (강동경희대학교병원 방사선종양학과) ;
  • 정미주 (강동경희대학교병원 방사선종양학과) ;
  • 최상현 (한국방사선의학연구소 방사선종양학과)
  • Jeong, Seonghoon (Department of Bio-convergence Engineering, Korea University) ;
  • Yoon, Myonggeun (Department of Bio-convergence Engineering, Korea University) ;
  • Kim, Dong Wook (Department of Radiation Oncology, Kyung Hee University at Gang Dong) ;
  • Chung, Weon Kuu (Department of Radiation Oncology, Kyung Hee University at Gang Dong) ;
  • Chung, Mijoo (Department of Radiation Oncology, Kyung Hee University at Gang Dong) ;
  • Choi, Sang Hyoun (Department of Radiation Oncology, Korea Institute of Radiological and Medical Sciences)
  • 투고 : 2015.12.01
  • 심사 : 2015.12.19
  • 발행 : 2015.12.31

초록

방사선치료는 수술, 항암치료와 함께 암의 3대 치료방법으로써 많은 암환자들이 방사선치료를 받게 된다. 최대한 많은 방사선을 암에 집중시키고 최대한 적은 방사선을 주변 정상 조직에 가해주기 위해 치료 전 치료계획을 철저히 세우고 품질 관리를 시행하지만 방사선치료가 잘못 시행되어 의도치 않은 방사선이 환자에게 전달되는 의료사고가 발생하기도 한다. 이를 해결하기 위해 환자 내부의 선량을 검증하기 위한 방법을 투과선량 측정을 통한 환자 내부선량의 역추정 방법이 제시되고 있다. 본 연구에서 제시한 투과선량을 이용한 환자선량 계산 방법을 거리역자승법칙, 심부선량백분율, scatter factor를 이용한 방법으로써 실제 환자 선량 평가 가능성에 대해 균질한 물등가 팬텀을 이용한 연구이다. 투과선량에 대한 이온함과 유리선량계의 교정 결과 유리선량계의 신호값이 이온함으로 측정한 선량값에 비해 6 MV에서 0.824, 10 MV에서 0.736배인 것으로 나타났고 scatter factor는 평균적으로 1.4정도인 것으로 확인되었다. 심부선량백분율 데이터를 사용하기 위해 Mayneord F factor를 적용하였으며 위의 정보들을 이용하여 균질한 팬텀에서 알고리즘을 검증한 결과 최대 오차 약 1.65%로 계산이 정확하게 실시됨을 확인하였다.

As radiation therapy is one of three major cancer treatment methods, many cancer patients get radiation therapy. To exposure as much radiation to cancer while normal tissues near tumor get little radiation, medical physicists make a radiotherapy plan treatment and perform quality assurance before patient treatment. Despite these efforts, unintended medical accidents can occur by some errors. In order to solve the problem, patient internal dose reconstruction methods by measuring transit dose are suggested. As feasibility study for development of patient dose verification system, inverse square law, percentage depth dose and scatter factor are used to calculate dose in the water-equivalent homogeneous phantom. As a calibration results of ionization chamber and glass dosimeter to transit radiation, signals of glass dosimeter are 0.824 times at 6 MV and 0.736 times at 10 MV compared to dose measured by ionization chamber. Average scatter factor is 1.4 and Mayneord F factor was used to apply percentage depth dose data. When we verified the algorithm using the water-equivalent homogeneous phantom, maximum error was 1.65%.

키워드

참고문헌

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피인용 문헌

  1. 반도체 선량계, 일반 선량계, 유리 선량계를 이용한 입사표면선량 모델 제시에 관한 연구: 몬테카를로 시뮬레이션 기반의 PCXMC 2.0을 통한 유효선량과 발병 위험도의 비교분석을 중심으로 vol.12, pp.2, 2018, https://doi.org/10.7742/jksr.2018.12.2.149