Positron Emission Tomography (PET)

SUVR stands for Standardized Uptake Value Ratio. It is a measure of the radiotracer uptake and/or binding in w a specific region normalized to a reference region. In rodent models, typical reference regions for brain PET SUVR analysis include whole brain, cerebellum, and brainstem.

A voxel (or volume element) is a pixel with a third-dimension. In brain imaging, rather than analyzing the data from an entire region-of-interest (ROI), we can perform statistical comparisons on a voxel-by-voxel basis. With this approach, we typically generate statistical parametric maps, such as t-statistic maps. Voxelwise analysis is often an excellent way to explore imaging data without a priori hypotheses.

PET and MRI complement each other. While MRI is typically used to glean information about brain structure or tissue biophysical properties, PET can provide information about brain metabolism and molecular neurobiology (e.g. receptor expression).

The spatial resolution of our PET scans are <1 mm. While that is lower than the resolution of MRI scans, it is still sufficient to evaluate measures, such as cerebral glucose metabolism, in different brain structures, such as the cerebral cortex, hippocampus, striatum, thalamus, olfactory bulb, cerebellum, and brainstem.