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

Purpose: The 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). Methods: A group of 40 children underwent 18F-FDG PET after being kept in the injection room at a constant temperature of 24 degree 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 degree C. Results: Uptake 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 degree C (p[Lt]0.002). Conclusion: Maintaining room temperature at a constant 24 degree C, half an hour prior to and during the period of FDG uptake significantly decreases accumulation of FDG in BAT in children.