MRS glucose mapping and PET joining forces: re-evaluation of the lumped constant in the rat brain under isoflurane anaethesia

The lumped constant (LC) is a correction factor employed to estimate the glucose metabolic rate (CMRglc) from the metabolic rate of a radioactive glucose analog such as F-18-fluorodeoxyglucose (FDG). By combining FDG positron emission tomography (PET) with magnetic resonance spectroscopic imaging (MRSI) of glucose dynamics, we determined the FDG LC in the rat brain under isoflurane anaesthesia.