Radiation exposure of radiographers who handle 18F-fluorodeoxyglucose for positron emission tomography at a hospital in Pretoria, South Africa

Abstract

¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) is used in most diagnostic applications of Positron Emission Tomography (PET). It has high annihilation energy of 511 keV, which results in potentially high radiation doses for staff. This study investigated radiographer radiation exposure during receipt, administration and scanning of patients with ¹⁸F-FDG. The objectives were to monitor the radiographers’ radiation levels throughout the handling of ¹⁸F-FDG; determine the radiation dose per radiographer per patient handling event and identify procedures which pose the greatest risk for radiation exposure. The study was quantitative, observational and prospective. Six radiographers’ work flow was tracked over time and the measured radiation doses were logged with electronic pocket dosimeters. The radiation dose per radiographer per event in the patient handling process was determined. The sample consisted of 1858 events, which were documented successfully. Events which posed the greatest risk for excessive radiation exposure were identified. The event in the patient handling process which lead to the highest radiation exposure was radiopharmaceutical injection, resulting in an average dose of 49.79 nSv/s. Radiographer 2 received the highest radiation dose per second (32.80 nSv/s) in her execution of the patient handling process and radiographer 3 the lowest, with 4.60 nSv/s. The average daily dose for the radiographers included in the study does not imply overexposure, but if the higher daily doses were extrapolated to yearly doses, half of the radiographers would be over the permitted annual limit.

Keywords: ¹⁸F-fluorodeoxyglucose (18F-FDG), radiographer, radiation exposure.