Brain [11C]PiB‐PET. The tracer has high affinity for β‐amyloid plaques. The PET scan is overlaid on CT and shows unspecific tracer retention in white matter, but no tracer binding in striate or cortex. Region of interest analysis also showed a normal cerebral to cerebellar cortical standardized uptake value (SUV) ration of 1.02 (normal < 1.5)