Analysis of Dose Distribution on Critical Organs for Radiosurgery with CyberKnife Real-Time Tumor Tracking System

사이버나이프 실시간 종양추적 시스템을 이용한 방사선수술 시 주요 장기의 선량분포 분석

  • Huh, Hyun-Do (Department of Radiation Oncology, College of Medicine, Inha University) ;
  • Choi, Sang-Hyoun (Department of Radiation Oncology, College of Medicine, Inha University) ;
  • Kim, Woo-Chul (Department of Radiation Oncology, College of Medicine, Inha University) ;
  • Kim, Hun-Jeong (Department of Radiation Oncology, College of Medicine, Inha University) ;
  • Kim, Seong-Hoon (Department of Radiation Oncology, College of Medicine, Hanyang University) ;
  • Ji, Young-Hoon (Department of Radiation Oncology, Korea Institute of Radiological and Medical Science) ;
  • Kim, Kum-Bae (Department of Radiation Oncology, Korea Institute of Radiological and Medical Science) ;
  • Lee, Sang-Hoon (Department of Radiation Oncology, College of Medicine, Kwandong Univerisity) ;
  • Choi, Jin-Ho (Department of Radiation Oncology, Gachon Medical School, Gil Medical Center) ;
  • Lee, Re-Na (Department of Radiation Oncology, School of Medicine, Ewha Womans University) ;
  • Shin, Dong-Oh (Department of Radiation Oncology, School of Medicine, Kyung Hee University)
  • 허현도 (인하대학교 의과대학 방사선종양학교실) ;
  • 최상현 (인하대학교 의과대학 방사선종양학교실) ;
  • 김우철 (인하대학교 의과대학 방사선종양학교실) ;
  • 김헌정 (인하대학교 의과대학 방사선종양학교실) ;
  • 김성훈 (한양대학교 의과대학 방사선종양학교실) ;
  • 지영훈 (원자력의학원 방사선의학연구센터 방사선종양학과) ;
  • 김금배 (원자력의학원 방사선의학연구센터 방사선종양학과) ;
  • 이상훈 (관동대학교 의과대학 방사선종양학교실) ;
  • 최진호 (가천의과학대학교 길병원 방사선종양학교실) ;
  • 이레나 (이화여자대학교 의학전문대학원 방사선종양학교실) ;
  • 신동오 (경희대학교 의학전문대학원 방사선종양학교실)
  • Published : 2009.03.31

Abstract

We measured the dose distribution for spinal cord and tumor using Gafchromic film, applying 3D and 4D-Treatment Planning for lung tumor within the phantom. A measured dose distribution was compared with a calculated dose distribution generated from 3D radiation treatment planning and 4D radiation treatment planning system. The agreement of the dose distribution in tumor for 3D and 4D treatment planning was 90.6%, 97.64% using gamma index computed for a distance to agreement of 1 mm and a dose difference of 3%. However, a gamma agreement index of 3% dose difference tolerence of and 2 mm distance to agreement, the accordance of the dose distribution around cord for 3D and 4D radiation treatment planning was 57.13%, 90.4%. There are significant differences between a calculated dose and a measured dose for 3D radiation treatment planning, no significant differences for 4D treatment planning. The results provide the effectiveness of the 4D treatment planning as compared to 3D. We suggest that the 4-dimensional treatment planning should be considered in the case where such equipments as Cyberknife with the real time tracking system are used to treat the tumors in the moving organ.

본 연구에서는 복부 전용 팬톰을 이용하여 폐 종양을 모델로 실시간 종양 추적 치료 시 종양에 대한 선량 분포와 종양 부근에 인접하여 상대적으로 움직임이 작은 주요장기인 척추의 선량 분포를 3차원과 4차원 전산화 치료계획을 통하여 나타난 선량분포에 대하여 Gafchromic 필름을 이용하여 선량을 비교평가 하였다. 비교 결과 종양의 선량 분포는 감마 지표 3%, 1 mm를 기준으로 일치도가 3차원 및 4차원에서 각각 90.6%, 97.64%이었고, 척추에서는 감마 지표 3%, 2 mm를 기준으로 3차원 및 4차원에서 각각 57.13%, 90.4%로 나타났다. 종양 및 척추에서 4차원 전산화치료계획 계산값은 측정값과 비교할 경우 근소한 차이를 보였으나 3차원 전산화 치료계획 시 종양에 근접하여 움직임이 작은 척추에서는 계산값과 측정값의 차이가 크게 나타났다. 따라서 사이버나이프와 같은 장비를 이용하여 호흡에 따라 움직이는 종양을 대상으로 실시간 종양추적 치료 시 4차원 전산화 치료계획이 반드시 필요하다고 사료된다.

Keywords

References

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