Regional glucose metabolic rates in the human brain: a PET study

With the purpose of determining the regional cerebral glucose metabolic rates (rCMRglu) in the normal human brain in resting state, we measured with PET and FOG, as the tracer, the distribution of regional radioactivity levels in the brains of seven young healthy volunteers. The individual brain images were stereotactically standardised with the help of a computerised brain atlas. In the next steps, the global cerebral glucose metabolic rate (gCMRglu) in the individual subjects was normalised to 34 mumol/ 100 g/min, followed by the averaging of the stereotactically standardised and metabolically normalised brain images across the subject population. In the final step, on the basis of high precision anatomical information, three-dimensional (3-D) volumes-of-interest (VOI's), covering over thirty anatomical structures in the brain, were created and the rCMRglu values inside the VOI's were determined in the averaged image. The present measurements of the rCMRglu values are in outstanding agreement with those determined in earlier quantitative PET-FDG studies, demonstrating that stereotactically standardised and metabolically normalised images of regional radioactivity distributions in the brain can be used for quantitative determination of rCMRglu values.