原子炉事故にともなう緊急時医療活動におけるスペクトロサーベイメータを用いた甲状腺¹³¹Iの測定

抄録

Feasibility for the use of the collimated NaI (Tl) scintillation spectrosurvey meter SS-γ C3475 (Hamamatsu Photonics) in the estimation of thyroidal ¹³¹I burden in patients that received emergency exposure to radioiodine (¹³¹I) is demonstrated. When the NaI (Tl) crystal probe collimated well to a neck phantom simulating the human thyroid gland, the detection limit of ¹³¹I deposited in that organ was estimated at 0.58kBq, which was well below the generally adopted screening level of 30kBq. The detection system for thyroidal ¹³¹I presented in this report is remarkably inexpensive compared to the conventional whole-body counters, and is considered to provide a satisfactorily accurate evaluation of thyroidal ¹³¹I burden.