Evaluation of Photoneutron During Radiation Therapy when Using Flattening Filter and Tracking Jaw with High Energy X-ray

고 에너지 X선 방사선치료 시 Flattening Filter와 Tracking Jaw 사용에 따른 광중성자 발생 평가

Park, Euntae;Jin, Seongjin;Park, Cheolwoo

  • Received : 2016.02.11
  • Accepted : 2016.02.29
  • Published : 2016.02.29


Radiation therapy is usually using linear accelerator and used X-ray energy is also getting higher. Recently linear accelerators has been developed 3F mode and tracking jaw technology and that was applied for patient therapy. This study aims at measuring photoneutrons depending on the use of 3F and tracking jaw system when radiation is irradiated using a linear accelerator. The generation of photoneutrons of 3F system was 70% smaller than 2F system and that of tracking jaw system was 83% higher than static jaw system. Photoneutron value is relatively low. However, it must be minimized for Photoneutron exposure during radiation therapy.


Linear accelerator;Flattening filter free;Tracking jaw;Photoneutron


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