Co-60 및 Ir-192 등의 방사성 동위원소가 비파괴 검사(Non-Destructive Test; NDT) 등의 분야에서 널리 쓰 임에 따라 방사선 안전관리가 매우 중요시되고 있다. 본 연구에서는 요오드화수은(Mercury(Ⅱ) Iodide; HgI2) 의 선원추적 시스템 적용 가능성을 평가하였다. HgI2로 제작된 Unit cell 센서의 신뢰도 검증을 위한 전기적 특성평가를 수행한 후, 방사선에 대한 센서의 위치의존성을 분석하고, Planning system의 선량 분포와 비교 하였다. 평가결과, R-sq>0.99 이상의 선형성과 CV<0.015 이하의 재현성을 보이며 신뢰도가 높은 것으로 나타났다. 또한, 위치의존성 평가에서는 센서의 isocenter에서 최댓값이 측정되었으며, 거리에 따라 점진적 감소를 나타냈다. 그러나 Planning system 상의 선량 분포 데이터와는 최대 30%의 차이를 보였는데, 센서는 단일지점으로부터 데이터를 수집하는 Planning system과 달리 면적으로부터 수집하기 때문으로 사료된다.

Radiation safety management is being considered very important since radioactive isotopes such as Co-60 and Ir-192 are widely used in fields such as non-destructive test(NDT). In this study, the applicability of Mercury(Ⅱ) Iodide(HgI2) source for tracing system was evaluated. To make sure the unit cell sensor’s reliability, we evaluated the electrical properties of the sensor made with HgI2, and then position dependence of the sensor was analyzed and compared with the dose distribution from the planning system. As a result of the evaluation, high reliability of the sensor was shown through the linearity of R-sq > 0.990 and reproducibility of CV < 0.015. In the position dependence evaluation, the maximum value was measured at the isocenter of the sensor and gradually decreased according to the distance. However, the dose distribution data from the planning system was turned out that has difference with that of the sensor up to 30%. This seems to come from the difference between single-point measuring based planning system and area measuring based sensor.

ABSTRACT
 Ⅰ. INTRODUCTION
 Ⅱ. MATERIAL AND METHODS
  1. Materials
  2. Fabrication
  3. Measurement
 Ⅲ. RESULT
  1. Linearity
  2. Reproducibility
  3. Position dependence
 Ⅳ. DISCUSSION
 Ⅴ. CONCLUSION
 Reference
 요 약

• Yohan Shin(Department of Radiation Oncology, Collage of Medicine, Inje University/Department of Medical Imaging Research Institute, Inje-university) | 신요한
• Moojae Han(Department of Radiation Oncology, Collage of Medicine, Inje University/Department of Medical Imaging Research Institute, Inje-university) | 한무재
• Jaehoon Jung(Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital) | 정재훈
• Kyotae Kim(Korea Institute of Radiological and Medical Sciences) | 김교태
• Yeji Heo(Department of Medical Imaging Research Institute, Inje-university) | 허예지
• Deukhee Lee(Department of Radiation Oncology, Busan Paik Hospital, Inje University) | 이득희
• Heunglae Cho(Department of Radiation Oncology, Busan Paik Hospital, Inje University) | 조흥래
• Sungkwang Park(Department of Radiation Oncology, Busan Paik Hospital, Inje University) | 박성광 Corresponding Author