Circadian Brown Adipose Tissue Metabolism

PET/CT is a hybrid imaging modality that allows imaging positron emitting isotopes such as F-18 along with anatomic imaging using x-rays. The physiologic information from the PET component is co-registered with the anatomic information from the CT component, permitting accurate localization and quantification of physiologic processes. The most common clinically used positron emitting radiopharmaceutical is F-18 fluorodeoxyglucose (FDG). It is a glucose analog which is taken up by glucose transporters and phosphorylated to FDG-6P by hexokinase. FDG PET/CT gives a map of relative amount of glucose uptake and phosphorylation over the interval from injection to scan.