A Clinical Trial Of The Evaluation Of Environmental Exposure In Yttrium 90 Radioembolization

Özet

The aim of this study is to measure the dose rate of two different forms of Y-90 microsphere used for radioembolization and to evaluate the results according to radiation safety regularities. 19 patients were enrolled in study (Age:61±1.5, F/M:12/7). As a result of the evaluation of the physicians, 7 patients were treated with TheraSphere and 12 patients were treated with SIR-Sphere. Dose rate measurements were taken at the stage of activity preparation, injection, radioactive wastes and discharge of patients using an electronic dosimeter (ED). The staff was exposed to dose rate of 1.3x10-4 μSv/MBq.h during activity preparation stage, 2.4x10-4 μSv/MBq.h in injection stage for Therapshere application. For SIR-spheres application, the staff was exposed to dose rate of 24.5x10-4 μSv/MBq.h during activity preparation stage, 10.1x10-4 μSv/MBq.h in injection stage. The average amount of dose received per operation was calculated 0.92±0.48 μSv in TheraSphere and 3.22±0.89 μSv in SIR-Spheres. For discharge of the patients, the average dose rate recorded from 1 m was found 4.0±0.28 μGy/h for TheraSphere and 3.2±0.15 μGy/h for SIRSpheres. The dose rate of radioactive wastes measured from the surface of the container which contained the radioactive wastes generated after the application was 0.5±0.1 μSv/h for TheraSphere and 1.1±0.08 μSv/h for SIR-Spheres. It is emphasized that Y-90 Therasphere application provides radiation safety more than SIR-Spheres because of its closed system, even so both applications shows low dose rate around the patient and short-term storage of radioactive wastes after application would be sufficient.