Constant ambient temperature of 24°C significantly reduces FDG uptake by brown adipose tissue in children scanned during the winter

PurposeThe aim of this study was to determine if warming patients prior to and during 18F-FDG uptake by controlling the room temperature could decrease uptake by brown adipose tissue (BAT).MethodsA group of 40 children underwent 18F-FDG PET after being kept in the injection room at a constant temperature of 24°C for half an hour before and 1 hour after intravenous tracer administration. The rate of uptake by BAT in this group was compared to the uptake in a control group of 45 patients who underwent PET when the injection room temperature was 21°C.ResultsUptake by BAT occurred in 5% of studies in the temperature-controlled room compared to 31% of studies performed when the injection room temperature was 21°C (p<0.002).ConclusionMaintaining room temperature at a constant 24°C, half an hour prior to and during the period of FDG uptake significantly decreases accumulation of FDG in BAT in children.