A novel approach for reduction of brown fat uptake on FDG PET

The aim of this study was to determine whether or not a single dose of a beta-blocker, such as propranolol 40 mg, administered 60 min prior to (18)F-fluorodeoxyglucose ((18)F-FDG) injection would help reduce brown fat uptake of (18)F-FDG. Patients who were referred for either a pre-treatment or a post-treatment evaluation positron emission tomography (PET) scan and who showed (18)F-FDG uptake in brown adipose tissue (BAT) were included in this study. The total number of patients who showed uptake in BAT and in whom a repeat study was carried out after propranolol injection was 40. A repeat PET scan was carried out after an interval of at least 48 h. Propranolol at a dose of 40 mg was given orally 60 min prior to the (18)F-FDG injection. A whole-body PET scan was performed on a dedicated whole-body PET scanner (ADVANCE, GE Medical Systems, Milwaukee, WI), using attenuation correction with 68-Ge external pin sources. We observed that (18)F-FDG uptake in BAT was absent in 36 (90%) patients post propranolol. We conclude that propranolol reduces the uptake of (18)F-FDG in BAT, and thus improves the accuracy of PET imaging.