Dynamic functional imaging of brain glucose utilization using fPET-FDG.

abstract Article history:Accepted 8 June 2014Available online 14 June 2014Keywords:2-[ 18 F]-fluorodeoxyglucose (FDG)Glucose utilizationVisual stimulusMR/PETPET Glucose is the principal source of energy for the brain and yet the dynamic response of glucose utilization tochanges in brain activity is still not fully understood. Positron emission tomography (PET) allows quantitativemeasurement of glucose metabolism using 2-[ 18 F]-fluorodeoxyglucose (FDG). However, FDG PET in its currentform provides an integral (or average) of glucose consumption over tens of minutes and lacks the temporal in-formation to capture physiological alterations associated with changes in brain activity induced by tasks ordrug challenges. Traditionally, changes in glucose utilization are inferred by comparing two separate scans,which significantly limits the utility of the method. We report a novel method to track changes in FDG metabo-lism dynamically, with higher temporal resolution than exists to date and within a single session. Using a con-stant infusion of FDG, we demonstrate that our technique (termed fPET-FDG) can be used in an analysispipeline similar to fMRI to define within-session differential metabolic responses. We use visual stimulation todemonstratethefeasibilityofthismethod.Thisnewmethodhasagreatpotentialtobeusedinresearchprotocolsand clinical settingssince fPET-FDGimaging can be performedwith mostPET scanners and data acquisition andanalysisarestraightforward.fPET-FDGisahighlycomplementarytechniquetoMRIandprovidesarichnewwayto observe functional changes in brain metabolism.© 2014 Elsevier Inc. All rights reserved.