Progress in Medical Physics (한국의학물리학회지:의학물리)

Korean Society of Medical Physics (한국의학물리학회)
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Characteristics of CCD Based Optical CT Scanner for Therapeutic Radiation Dosimetry

치료방사선량평가를 위한 CCD 기반 광학컴퓨터단층촬영 스캐너의 특성

  • Lee, Jae Choon (Department of Medical Physics, Kyonggi University) ;
  • Kim, Ae Ran (Department of Medical Physics, Kyonggi University) ;
  • Ji, Young Hoon (Korea Institute of Radiological and Medical Sciences) ;
  • Kwon, Soo-Il (Department of ElectroPhysics, College of Natural Science, Kyonggi University)
  • 이재춘 (경기대학교 대학원 의학물리학과) ;
  • 김애란 (경기대학교 대학원 의학물리학과) ;
  • 지영훈 (한국원자력의학원) ;
  • 권수일 (경기대학교 자연과학대학 전자물리학과)
  • Received : 2016.05.30
  • Accepted : 2016.06.04
  • Published : 2016.06.30
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Abstract

A CCD camera and an LED light source were combined to fabricate a compact optical CT scanner for the therapeutic radiation dose evaluation of a polymer gel dosimeter. After the collimated beam emitted by the LED passed through aquarium, gel phantom, and telecentric lens, an image was collected by the CCD camera and reconstructed using MATLAB. By using a stepping motor and LabVIEW, the gel dosimeter was rotated at every $0.72^{\circ}$, and the time for collecting 500 slice images per a revolution was within 20 min. At a spatial frequency of 4.5 lp/mm of the optical CT scanner, the modulation transfer function value was 72%. The linear correlation coefficient of the optical CT scanner for the polymer gel dosimeter was 0.987.

중합체 겔 선량계의 치료방사선 선량 평가를 위해 CCD 카메라와 LED 광원을 결합하여 소형 광학컴퓨터단층촬영 스캐너를 제작하였다. LED에서 나온 평행 빔은 아쿠아리움, 겔 팬텀, 텔레센트릭 렌즈를 통과한 후 CCD 카메라로 영상이 수집되었으며, MATLAB을 이용하여 영상을 재구성하였다. 겔 선량계는 구동 모타와 LabVIEW를 이용하여 $0.72^{\circ}$씩 회전시키었으며, 1회전 당 500장의 슬라이스 영상을 얻는데 걸린 시간은 20분 이내였다. 제작한 광학컴퓨터단층촬영 스캐너의 공간주파수 4.5 lp/mm에서 MTF값은 72%이었다. 중합체 겔 선량계의 광학컴퓨터단층촬영 스캐너의 선형상관계수 $r^2$ 값은 0.987이었다.

Keywords

References

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