Accuracy Evaluation of CyberKnife $Synchrony^{TM}$ Respiratory Tracking System Using Phantom

Phantom을 이용한 사이버나이프 $Synchrony^{TM}$ 호흡 추적장치의 정확성 평가

  • Kim, Gha-Jung (Department of Radiological Oncology, Konyang University Hospital) ;
  • Bae, Seok-Hwan (Department of Radiological Science, Konyang University) ;
  • Lim, Chang-Seon (Department of Radiological Science, Konyang University) ;
  • Kim, Chong-Yeal (Department of Radiological Science & Technology, Chonbuk National University)
  • 김가중 (건양대학교병원 방사선종양학과) ;
  • 배석환 (건양대학교 방사선학과) ;
  • 임창선 (건양대학교 방사선학과) ;
  • 김종일 (전북대학교 방사선과학기술학과)
  • Published : 2009.09.30


This study was conducted to evaluate the accuracy of CyberKnife $Synchrony^{TM}$ respiratory tracking system which was applied to Stereotactic Radiosurgery (SRS) for moving tumors in chest and abdomen with breathing motion. For accurate evaluation, gold fiducial marks were implanted into a moving phantom. The moving phantom was a cube imbedding an acryl ball as a target. The acryl ball was prescribed to 20 Gy at 70% of isodose curve in a virtual treatment and radiochromic films were inserted into the acryl ball for dose verification and tracking accuracy evaluation. The evaluation of position tracking consists of two parts: fiducial mark tracking in a stationary phantom and $Synchrony^{TM}$ respiratory tracking in a moving phantom. Each measurement was done in three directions and was repeated to 5 times. Range of position error was 0.1957 mm to 0.6520 mm in the stationary phantom and 0.4405 mm to 0.7665 mm in the moving phantom. Average position error was 0.3926 mm and 0.5673 mm in the stationary phantom and the moving phantom respectively. This study evaluates the accuracy of CyberKnife $Synchrony^{TM}$ Respiratory tracking system, and confirms the usefulness when it's used for Stereotactic Radiosurgery of body organs.


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