Production, administration and disposal of cyclotron produced shortlived radioactive gases for positron emission tomography studies at the Austin Repatriation Medical Centre, Melbourne

Positron Emission Tomography (PET) Centre is operational at the Austin Repatriation Medical Centre, Melbourne. The major equipment consists of a 10 MeV cyclotron and a whole body PET scanner. Radioactive gases produced and used directly in clinical studies include [15O]O2, [15O]CO, and [15O]CO2, whilst [11C]CO2 is also produced for use in radiochemistry syntheses. Radioactivity delivery rates of 3.7, 3.3, and 1.6 GBq/min to the scanner suite have been achieved for [15O]O2, [15O]CO2, and [15O]CO respectively, and batch productions of 36.3 GBq of [11C]CO2 have been produced. The production. patient administration and disposal of the short-lived radioactive gases has been achieved in compliance with radiation protection principles. Radioactive gas doses of 1.7 GBq are administered to patients with less than 0.02 MBq/m3 leakage into the scanner suite. Less than 13 MBq of [ 15O]-labelled gases are released into the environment per patient study at a concentration of 0.018 MBq/m3. Annually less than 2 GBq is expected to be released into the environment. The centre design and first four months' experience of radioactive gas production, administration and disposal is presented. 5 refs., 4 tab., 1 fig