The investigator decided not to pursue the study.

The overall aim of this project is to implement a non-invasive method of measuring quantitative regional cerebral blood flow (rCBF) on the UAB hybrid PET/MRI scanner to allow conducting such [O-15]water based scans with relative ease and safety in a large variety of important clinical and research applications. Participants will undergo imaging at baseline and after administration of a drug to increase cerebral blood flow to evaluate perfusion estimates during low and high flow states. The goal of this study is to generate data that will justify eliminating invasive arterial sampling in most [O-15]water-based PET protocols.

Inclusion Criteria:

• Six participants aged 19-60 years of age, male and female, with no evidence of neurological disease, will be recruited from UAB and the surrounding community.

Exclusion Criteria:

• Participants will be excluded if there is any evidence or history of claustrophobia or the subject has metallic implants or devices that are normally exclusion factors for MRI.