Progress in Medical Physics (한국의학물리학회지:의학물리)

Korean Society of Medical Physics (한국의학물리학회)
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Estimate of Radiation Doses in MDCT Using Patient Weight

MDCT 검사에서 환자 체중을 이용한 선량 평가

  • Kwon, Seong-Ohk (Department of Radiology, Asan Medical Center) ;
  • Dong, Kyung-Rae (Department of Radiological Technology, Gwangju Health College University) ;
  • Kweon, Dae-Cheol (Department of Radiologic Science, Shin Heung College University) ;
  • Goo, Eun-Hoe (Department of Radiology, Seoul National University Hospital) ;
  • Choi, Ji-Won (Department of Radiological Science, Jeonju University) ;
  • Chung, Woon-Kwan (Department of Nuclear Engineering, Chosun University)
  • 권성욱 (서울아산병원 영상의학팀) ;
  • 동경래 (광주보건대학 방사선과) ;
  • 권대철 (신흥대학 방사선과) ;
  • 구은회 (서울대학교병원 영상의학) ;
  • 최지원 (전주대학교 방사선학과) ;
  • 정운관 (조선대학교 원자력공학과)
  • Received : 2010.06.09
  • Accepted : 2010.09.13
  • Published : 2010.09.30
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Abstract

The purpose of this study provides measurements of radiation dose from MDCT of head, chest, abdomen and pelvic examinations. A series of dose quantities that are measured of patient weight to compare the dose received during MDCT examinations. Data collected included: weight together with CT dose descriptors, volume CT dose index (CTDIvol) and dose length product (DLP). The effective dose was also estimated and served as collective dose estimation data. Data from 1,774 adult patients attending for a CT examination of the head (n=520) or chest (n=531) or abdomen (n=724) was obtained from spiral CT units using a same CT protocol. Mean values of CTDIvol was a range of 48.6 mGy for head and 6.9, 10.5 mGy for chest, abdomen examinations, respectively. And mean values of DLP was range of 1,604 $mGy{\cdot}cm$ for head, 250 $mGy{\cdot}cm$ for chest, 575 $mGy{\cdot}cm$ for abdomen examinations, respectively. Mean effective dose values for head, chest, abdominal CT were 3.6, 4.2, and 8.6 mSv, respectively. The degree of CTDIvol and DLP was a positive correlation with weight. And there was a positive correlation for weight versus CTDIvol ($r^2$=0.62), DLP ($r^2$=0.694) in chest. And head was also positive correlation with weight versus CTDIvol ($r^2$=0.691), DLP ($r^2$=0.741). We conclude that CTDIvol and DLP is an important determinant of weight within the CT examinations. The results for this study suggest that CT protocol should be tailored according to patient weight.

환자가 두부, 흉부, 복부 MDCT 검사에서 피폭되는 선량을 평가하였다. 선량의 지표는 CTDIvol, DLP, 유효선량을 평가하여 환자의 체중과 선량과의 상관관계를 분석하였다. CT 검사에서 검사 조건을 동일하게 하여 연속적으로 두부(520명), 흉부(531명), 복부(724명) 환자를 대상으로 하였다. CTDIvol과 DLP 평균선량은 두부검사에서 CTDIvol (48.6 mGy), DLP (1,604 $mGy{\cdot}cm$), 흉부검사에서 CTDIvol (6.9 mGy), DLP (250 $mGy{\cdot}cm$), 복부는 CTDIvol (10.5 mGy), DLP (575 $mGy{\cdot}cm$), 유효선량은 두부, 흉부, 복부에서 3.6, 4.2, 8.6 mSv로 분석되었다. 환자의 체중과 선량과의 상관분석에서 두부, 흉부, 복부에서, 두부는 상관관계가가 보이지 않았고, 흉부는 CTDIvol ($r^2$=0.62), DLP ($r^2$=0.694), 복부는 CTDIvol ($r^2$=0.691), DLP ($r^2$=0.741)와 양의 상관관계를 나타내냈다. 검사에 따른 체중과의 상관관계를 이해하고 검사 하면 방사선 피폭에 의한 선량을 평가하고 관리하는데 기여 할 수 있을 것이다.

Keywords

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