Development of Dose Verification Method for In vivo Dosimetry in External Radiotherapy

방사선치료에서 투과선량을 이용한 체내선량 검증프로그램 개발

  • Hwang, Ui-Jung (Department of Radiation Oncology, National Medical Center) ;
  • Baek, Tae Seong (Department of Bio-convergence Engineering, Korea University) ;
  • Yoon, Myonggeun (Department of Bio-convergence Engineering, Korea University)
  • 황의중 (국립중앙의료원 방사선종양학과) ;
  • 백태성 (고려대학교 바이오융합공학과) ;
  • 윤명근 (고려대학교 바이오융합공학과)
  • Received : 2014.02.28
  • Accepted : 2014.03.13
  • Published : 2014.03.31


The purpose of this study is to evaluate the developed dose verification program for in vivo dosimetry based on transit dose in radiotherapy. Five intensity modulated radiotherapy (IMRT) plans of lung cancer patients were used in the irradiation of a homogeneous solid water phantom and anthropomorphic phantom. Transit dose distribution was measured using electronic portal imaging device (EPID) and used for the calculation of in vivo dose in patient. The average passing rate compared with treatment planning system based on a gamma index with a 3% dose and a 3 mm distance-to-dose agreement tolerance limit was 95% for the in vivo dose with the homogeneous phantom, but was reduced to 81.8% for the in vivo dose with the anthropomorphic phantom. This feasibility study suggested that transit dose-based in vivo dosimetry can provide information about the actual dose delivery to patients in the treatment room.


Supported by : National Research Foundation of Korea


  1. Boellaard R, M. van Herk, Mijnheer BJ: A convolution model to convert transmission dose images to exit dose distributions. Medical Physics 24:189-200 (1997)
  2. Ronald Boellaard, Marion Essers, Marcel van Herk, Ben J. Mijnheer: New method to obtain the midplane dose using portal in vivo dosimetry. Int J Rad Oncol Biol Phys 41(2):465-474 (1998)
  3. Louwe RJW, Damen EMF, M. van Herk, Minken AWH, Torzsok O, Mijnheer BJ: 3D dose reconstruction of breast cancer treatment using portal imaging. Medical Physics 30: 2376-2398 (2003)
  4. WJC van Elmpt, Nijsten SMJJG, Mijnheer BJ, Minken AWH: Experimental verificaiton of a portal dose prediction model. Medical Physics 32:2805-2818 (2005)
  5. Markus Wendling, Robert J. W. Louwe, Leah N. McDermott, Jan-Jakob Sonke, Marcel van Herk, Ben J. Mijnheer: Accurate two-dimensional IMRT verification using a back-projection EPID dosimetry method. Medical Physics 33(2): 259-336 (2006)
  6. Wouter J. C. van Elmpt, Sebastiaan M. J. J. G. Nijsten, Robert FH, et al: Monte Carlo based 3D dose reconstruction method derived from portal dose images. Medical Physics 33(7):2426-2478 (2006)
  7. Louwe RJW, Wendling M, MB van Herk, Mijnheer BJ: 3D heart dose reconstruction to estimate normal tissue complication probability after breast irradiation using portal dosimetry. Medical Physics 34(4):1354-1371 (2007)
  8. Markus Wendling, Leah N. McDermott, Anton Mans, Jan-Jakob Sonke, Marcel van Herk, Ben J. Mijnheer: Simple backprojection algorithm for 3D in vivo EPID dosimetry of IMRT treatments. Medical Physics 36(7):3310-3321 (2009)
  9. Faiz M. Khan: The Physics of Radiation Therapy. 4th ed, Williams & Wilkins, Baltimore, MD (2010), pp. 146-148
  10. Daniel a. Low, James F. Dempsey: Evaluation of the gamma dose distribution comparison method. Medical Physics 30(9):2455-2464 (2003)
  11. Janusz Winiecki, kTomasz Morgas, Karolina Majewaska, Barbara Drzewiecka: The gamma evaluation method as a routine QA procedure of IMRT. Reports of Practical Oncology & Radiotherapy 14(5):162-168 (2009)