To provide a radioactivity quantity detecting sensor, a radioactivity quantity measuring method using this sensor, and a radioactive medicine automatic dosing apparatus not requiring a long time before dosage due to radioactivity quantity measurement in automatically dosing a radioactive medicine to eliminate the exposure to a medical person.
A vial 3 storing the liquid radioactive medicine is enclosed in a radiation shielding container 13, and an extraction needle 7 is thrusted into an opening of the vial 3 in the removed state of a cap of the radiation shielding container 13. In this state, the radioactive medicine is sucked by a syringe 25 through a passage 23 connected to the thrusted extraction needle 7. In the structure of the radioactivity quantity detecting sensor 19, a photomultiplier tube 52 is connected to the end of a light guide connected to the outer periphery of an annular scintillator 49 through which the passage 23 passes, and the outer surfaces of the scintillator 49 and light guide are covered with a reflector 59. The integrated count value of radioactivity detected by the radioactivity quantity detecting sensor 19 is divided by the integrated time of performing this detection and divided by different detecting efficiency by a radioactive ray source to measure the actual quantity of radioactivity of the dosed radioactive medicine.
FUJII TAKASHI
SAITO KAZUHIRO
SD GIKEN KK