Brain

Normal brain

Because the brain preferentially uses glucose as its energy source, whole body images at 1-2 hours after injection of FDG will almost always demonstrate prominent activity in the brain. Gray matter is particularly FDG-avid with uptake levels similar to that seen in malignancy. Therefore, detection of brain malignancies, particularly in gray matter, is limited with FGD PET. Activity in areas previously treated with surgery or radiation may be lower in intensity than that within normal brain. Hypometabolism is also typical in epileptogenic foci during the interictal period. FDG activity may also be decreased in one or both frontotemporoparietal association complexes in Alzheimer’s dementia.

© 2006 by the Rector & Visitors of the University of Virginia