Figure 4:

Example of the importance of simultaneity for PET/MRI. 72 year-old female with Stage IV lung cancer and altered mental status. The MRI was performed about 1 week prior to the PET scan. During the MRI scan, the patient has marked CBF increase in the right frontal lobe consistent with a peri-ictal state (yellow arrows). This was controlled by the time of the FDG PET scan, which shows normal metabolism in this region. This illustrates that simultaneity is important for the goals of image prediction, since the assumption is that the patient is in the same physiological state.