대한방사선기술학회지:방사선기술과학 (Journal of radiological science and technology)

  • 제39권1호
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  • Pages.99-105
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  • 2016
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  • 2288-3509(pISSN)
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  • 2384-1168(eISSN)
대한방사선과학회 (Korean Society of Radiological Science)
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방사선치료시 전자포털영상장치를 이용한 잡음전력스펙트럼 방법론 측정비교

Comparison of Noise Power Spectrum Methodologies in Measurements by Using Various Electronic Portal Imaging Devices in Radiation Therapy

  • 손순룡 (원광보건대학교 방사선과) ;
  • 최관우 (서울아산병원 영상의학과) ;
  • 정회원 (백석문화대학교 방사선과) ;
  • 권경태 (동남보건대학교 방사선과) ;
  • 김기원 (강동경희대병원 영상의학과) ;
  • 이영아 (신구대학교 바이오 동물학과) ;
  • 손진현 (신구대학교 방사선과) ;
  • 민정환 (신구대학교 방사선과)
  • Son, Soon-Yong (Dep. of Radiological Technology, Wonkwang Health Science University) ;
  • Choi, Kwan-Woo (Dep of Radiology, Asan Medical Center) ;
  • Jeong, Hoi-Woun (Dep. of Radiological Technology, Baekseok Culture University College) ;
  • Kwon, Kyung-Tae (Dep. of Radiological Technology, Dongnam Health University) ;
  • Kim, Ki-Won (Dep. of Radiology, Kyung Hee University Hospital at Gang-dong) ;
  • Lee, Young-Ah (Dep. of Bio-Technologist and Laboratory Animal, Shingu University College) ;
  • Son, Jin-Hyun (Dep. of Radiological Technology, Shingu University College) ;
  • Min, Jung-Whan (Dep. of Radiological Technology, Shingu University College)
  • 투고 : 2016.01.27
  • 심사 : 2016.03.07
  • 발행 : 2016.03.31
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초록

잡음전력스펙트럼 (noise power spectrum, NPS)는 noise 진폭의 측정과 균일한 방사선 영역으로부터 획득된 영상의 품질에 가장 일반적인 방법 중 하나이다. 이 연구의 목적은 megavoltage X-ray 에너지를 사용하여 다른 잡음 전력스펙트럼 방법론들을 비교하는 것이다. 진단 영역에서의 잡음전력스펙트럼 평가 방법들은 국제 전기 규격 international electro-technical commission(IEC 62220-1) 기준을 사용하여 치료 영역에 적용되었다. 우리가 사용한 전자포털영상장치(electronic portal imaging device, EPID)는 Varian TrueBeam$^{TM}$, Siemens BEAMVIEW$^{PLUS}$, Elekta iViewGT 그리고 Varian Clinac$^R$ iX aS1000이었다. 잡음전력스펙트럼의 관심영역을 측정하기 위해, 우리는 겹침 (overlapping), 비겹침 (non-overlapping), 평탄도 (flatness), 반음영 (penumbra) 4가지 인자를 사용하였다. 결과적으로는 Siemens BEAMVIEW$^{PLUS}$, Varian TrueBeam$^{TM}$ flattening filter, Varian Clinac$^R$ iX aS1000, Varian TrueBeam$^{TM}$ flattening filter free에서의 잡음 (noise) 분포는 기존의 첫번째, 두번째, 세번째 실험방법보다는 Elekta iViewGT보다 현격하게 높은 noise 분포가 나타남을 알 수 있다. 이번 연구는 다양한 인자들이 잡음전력스펙트럼의 megavoltage imaging (MVI)영상에서 MVI영역에서 잡음전력 스펙트럼의 기준의 방법론으로 사용되어질 수 있다는 것을 보여주었다.

The noise power spectrum (NPS) is one of the most general methods for measuring the noise amplitude and the quality of an image acquired from a uniform radiation field. The purpose of this study was to compare different NPS methodologies by using megavoltage X-ray energies. The NPS evaluation methods in diagnostic radiation were applied to therapy using the International Electro-technical Commission standard (IEC 62220-1). Various radiation therapy (RT) devices such as TrueBeam$^{TM}$(Varian), BEAMVIEW$^{PLUS}$(Siemens), iViewGT(Elekta) and Clinac$^R$ iX (Varian) were used. In order to measure the region of interest (ROI) of the NPS, we used the following four factors: the overlapping impact, the non-overlapping impact, the flatness and penumbra. As for NPS results, iViewGT(Elekta) had the higher amplitude of noise, compared to BEAMVIEW$^{PLUS}$ (Siemens), TrueBeam$^{TM}$(Varian) flattening filter, Clinac$^{R}$iXaS1000(Varian) and TrueBeam$^{TM}$(Varian) flattening filter free. The present study revealed that various factors could be employed to produce megavoltage imaging (MVI) of the NPS and as a baseline standard for NPS methodologies control in MVI.

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참고문헌

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