Manufacture of Immobilization Device (Vac-lok) and the Usefulness of Evaluation for Reproducibility of Patients in the Radiotherapy

환자의 재현성을 위한 고정장치(Vac-lok) 제작과 방사선치료에서 유용성 평가

  • Lee, Jae-Seung (Department of Radiation Oncology, Good Samaritan Hospital) ;
  • Kim, Gyoung-Hee (Department of Radiologic Technology, Sunlin University) ;
  • Jeong, Kyu-Hwan (Department of Radiologic Technology, Sunlin University) ;
  • Kweon, Dae-Cheol (Department of Radiologic Science, Shin Heung College University) ;
  • Goo, Eun-Hoe (Department of Radiology, Seoul National University Hospital) ;
  • Park, Cheol-Woo (Department of Radiological Technology, Dong Eui Institute of Technology) ;
  • Im, In-Chul (Department of Radiological science, Dong Eui University) ;
  • Dong, Kyung-Rae (Department of Radiological Technology, Gwangju Health College University) ;
  • Chung, Woon-Kwan (Department of Nuclear Engineering, Chosun University)
  • 이재승 (선린의료원 방사선종양학과) ;
  • 김경희 (선린대학 방사선과) ;
  • 정규환 (선린대학 방사선과) ;
  • 권대철 (신흥대학 방사선과) ;
  • 구은회 (서울대학교병원 영상의학과) ;
  • 박철우 (동의과학대학 방사선과) ;
  • 임인철 (동의대학교 방사선학과) ;
  • 동경래 (광주보건대학 방사선과) ;
  • 정운관 (조선대학교 원자력공학과)
  • Received : 2011.01.26
  • Accepted : 2011.03.22
  • Published : 2011.03.30


We manufactured the Vac-lok that can be applied to patient of special body shape and need to special set-up position and evaluated the usefulness in the radiation therapy. The manufacture Vac-lok, It was used EVA resin and biobeadform of a diameter 1.5 mm. carried out the test of functionality, structural and analyzed the relative reproducibility of phantoms and patients. During the total period of radiation therapy, Vacuum pressure bring variety to a very small amount in the test of functionality of the manufacture Vac-lok. But It was a negligible quantity. The manufacture Vac-lok improved the relative reproducibility of phantoms than the existing Vac-lok and tolerance has a confidence less than 4% error. Also, relative reproducibility of patient increased error than phantom in the antero-posterior and lateral plan. However, the maximum set-up error was less than ${\pm}\;2.3$ mm. In conclusion, If tolerance set-up error of radiotherapy is less than ${\pm}\;3$ mm, the manufacture Vac-lok was enough possible to use and improvement of reproducibility, considering supply with the Vac-lok made to measure of special patient that produced at a low price and without delay.


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