Radiation exposure to PET technologists at the Austin and Repatriation medical centre

Full text: The use of Positron Emission Tomography (PET) in Australia has grown rapidly in the last few years. PET's unique ability to demonstrate physiologic processes such as glucose metabolism has enabled it to become a routine part of patient management, particularly in oncology. At the Centre for PET the increase in patient numbers over the last two years led to a detailed review of the radiation exposure to staff, in particular the technologists, and comparison of radiation doses to staff involved in general nuclear medicine. A review of radiation doses over the past two years measured by Thermoluminescent Detectors (TLD) was performed for both PET and Nuclear Medicine Technologists in the Department. Data generated showed that the radiation exposure to PET technologists was higher, with an average of 789μSv per quarter, than the average dose to those technologists performing scans with lower energy isotopes (average 499μSv per quarter). Despite an increase in PET patient numbers over the two-year period (from 850 clinical and research studies to 1070), and an average dose of 400MBq (10mCi) 18F-FDG per patient, no corresponding increase in technologist dose was observed. Restriction in technologist dose was achieved through increased efficiency in patient interaction, remote monitoring of patients after injection and while scanning, and adequate shielding of injections. Although these readings are well within the maximum recommended dose of 20 000 (Sv/year), further improvements to radiation safety are planned, including increased syringe shielding and remote injection of patients. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc