Figure 3.

An example of [¹⁵O]Water Positron Emission Tomography (PET). The image is scaled in activity units (kBq/cc). The image was created by summing the first 40 seconds immediately post-bolus transit from a dynamic imaging sequence initiated at the time of [¹⁵O]water injection. The image is a semi-quantitative representation of the cerebral blood flow (CBF) at the time of bolus arrival in the brain. The color bar describes increasing blood flow with increasing signal intensity (from black to red).