Studies on Dose Distribution and Treatment Technique of High Energy Electron

고(高)에너지 전자선(電子線) 치료(治療)를 위(爲)한 선량분포(線量分布) 및 기술적(技術的) 문제(問題)의 연구(硏究)

  • Lee, D.H. (Department of Radiology and Nuclear Medicine, Yonsei University College of Medicine) ;
  • Chu, S.S. (Department of Radiology and Nuclear Medicine, Yonsei University College of Medicine)
  • 이도행 (연세대학교 의과대학 방사선과학교실) ;
  • 추성실 (연세대학교 의과대학 방사선과학교실)
  • Published : 1978.06.30


High energy electron beams took effect for tumor radio-therapy, however, had a lot of problems in clinical application because of various conversion factors and complication of physical reactions. Therefor, we had experimentally studied the important properties of high energy electron beams from the linear accelerator, LMR-13, installed in Yonsei Cancer Center. The results of experimental studies on the problems in the 8, 10, 12 Mev electron beam therapy were reported as following. 1. On the measurements of the outputs and absorbed doses, the ionization type dosimeters that had calibrated by $^{90}Sr$ standard source were suitable as under 3% errors for high energy electrons to measure, but measuring doses in small field sizes and the regions of rapid fall off dose with ionization chambers were difficult. 2. The electron energy were measured precisely with energy spectrometer consisted of magnet analyzer and tele-control detector and the practical electron energy was calculated under 5% errors by maximum range of high energy electron beam in the water. 3. The correcting factors of perturbated dose distributions owing to radiation field, energy and material of the treatment cone were checked and described systematically and variation of dose distributions due to inhomogeneous tissues and sloping skin surfaces were completely compensated. 4. The electron beams, using the scatterers; ie., gold, tin, copper, lead, aluminium foils, were adequately diffused and minimizing the bremsstrahlung X-ray induced by the electron energy, irradiation field size and material of scatterers, respectively. 5. Inproving of the dose distribution from the methods of pendulum, slit, grid and focusing irradiations, the therapeutic capacity with limited electron energy could be extended.