6. PET Imaging of Neurotransmitter Systems: quantification

COEX 

After preprocessing, PET data consists of time series of radioactivity concentrations in each region of the brain called time activity curves (TACs). Full quantification of PET data involves fitting pharmacokinetic models to these TACs in each target region, or voxel, in order to estimate scalar outcome measures, e.g. binding potential, which serve as proxies for the concentrations of neurotransmitter receptors and transporters. In this tutorial, I will outline some of the relevant practical considerations for PET quantification such as choosing an appropriate model and outcome measure, as well as providing a hands-on demonstration of how these models can be fitted to TAC data to derive estimates of binding using open-source tools including bloodstream and kinfitr. I will also discuss examples of how these modeled PET outcomes can be combined with data from functional magnetic resonance imaging (fMRI), electroencephalography (EEG) and diffusion weighted imaging (DWI) to facilitate a multimodal view of brain structure and function. Altogether this will provide attendees with the basics required to be able to begin to perform all stages of PET analysis from images, to estimates of receptor and transporter concentrations, to their integration with other brain imaging data.