대한방사선기술학회지:방사선기술과학 (Journal of radiological science and technology)

  • 제40권3호
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  • Pages.385-392
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  • 2017
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  • 2288-3509(pISSN)
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  • 2384-1168(eISSN)
대한방사선과학회 (Korean Society of Radiological Science)
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전산화단층촬영에서 관전압과 관전류, 통계적 반복재구성법에 따른 화질과 피폭선량

Quality of Image and Exposure Dose According to kVp, mA and Iterative Reconstruction in Computed Tomography

  • 차상영 (인하대병원 영상의학과) ;
  • 박재윤 (인천기독병원 영상의학과) ;
  • 이용기 (동남보건대학교 방사선과) ;
  • 김정훈 (건양대학교병원 방사선종양학과) ;
  • 최재호 (안산대학교 방사선과)
  • Cha, Sang-Young (Department of Radiology, Inha University Hospital) ;
  • Park, Jae-Yoon (Department of Radiology, Incheon Christian Hospital) ;
  • Lee, Yong-Ki (Dept. of Radiological Technology, DongNam Health University) ;
  • Kim, Jeon-Hun (Department of Radiatioin Oncology, Konyang University Hospital) ;
  • Choi, Jae-Ho (Department of Radiological Technology, Ansan University)
  • 투고 : 2017.03.18
  • 심사 : 2017.09.13
  • 발행 : 2017.09.30
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초록

본 연구는 전산화단층촬영에서 관전압과 관전류에 따른 화질과 피폭선량을 연구하고 None IR과 IR (Iterative Reconstruction)의 단계에 따른 영상의 SNR(Signal to Noise Ratio)을 비교하여 영상 화질의 개선정도에 대하여 확인해보고자 하였다. Image J를 이용하여 화질을 측정한 결과 관전압의 증가에 따라 HU (Hounsfield units)와 BN(Background Noise)은 감소하였으며, 이와 반대로 SI (Signal Intensity)와 SNR, $CTDI_{vol}$ (CT dose in dex volume)은 관전압이 높아질수록 증가하였으며, BHU(Background Hounsfield Units)의 변화는 없었다. 관전류의 증가로 인해서 BN이 감소하였고, 반대로 SNR과 CTDI은 증가하였다. 또한 IR의 단계가 높아질수록 HU와 SI, BN이 낮아지고, SNR이 약 10~60% 향상됨을 알 수 있었다. 이를 토대로 임상에서 IR 적용 시 단계적 접근 방식으로 관전압과 관전류를 미세 조정하여 점차적으로 방사선량을 줄여 나가야 할 것이다.

The purpose of this study is to investigate the image quality and exposure dose according to kVp and mAs in CT and to confirm improvement in image quality according to None IR and IR(Iterative Reconstruction) levels. Measurement results of image quality using Image J, HU(Hounsfield units) and BN(Background Noise) are decreased, while SNR(Signal to Noise Ratio) and $CTDI_{vol}$(CT dose index volume) are increased as the kVp increases and there was no change of BHU(Background Hounsfield units). BN was reduced due to increased kVp, while SNR and $CTDI_{vol}$ were increased. Also, the higher IR stage, the lower BN, SI(Signal Intensity) and HU while SNR was improved by about 10~60%. Based on this, when applying IR for clinical applications, it is necessary to finely adjust kVp and mA with a phased approach.

키워드

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