한국의학물리학회:학술대회논문집 (Proceedings of the Korean Society of Medical Physics Conference)
- 한국의학물리학회 2002년도 Proceedings
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- Pages.300-301
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- 2002
Determination of Relative Output Factors Using PinPoint Ion Chamber and Gafchromic Film in Gamma Knife
- Seo, Weon-Seop (Dept. of Neurosergery, School of Medicine, Kyunghee University) ;
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Shin, Dong-Oh
(Dept. of Radiation Oncology, School of Medicine, Kyunghee University)
;
- Lim, Young-Jin (Dept. of Neurosergery, School of Medicine, Kyunghee University) ;
- Im, Yong-Seok (Dept. of Neurosergery, Samsung Medical Center)
- 발행 : 2002.09.01
초록
Of many modalities for measuring output factor, we measured the outputs of 18mm, 14mm, 8mm and 4mm helmet in Gamma knife using ion chambers and a Gafrcromic MD-55 film and normalized the outputs of four helmets the one of a 18mm helmet. Ion chambers used for this paper were a PR-05P and a PinPoint having a volume of 0.07cc and 0.015cc respectively. The recommended output factors from a manufacture were 1, 0.984, 0.956, and 0.87. For PR-05P, the output factor of 14mm helmet showed a good agreement, but the ones of 8mm and 4mm helmet showed the difference of 4.6% and 47% respectively. For PinPoint, The output factors of 14mm and 8mm helmet showed a good agreement, but the one of a 4mm helmet showed a difference of 18%. The Gafcromic MD-55, however, showed a good agreement for all helmets.