Continuation of The Kronos Early Estrogen Prevention Study (KEEPS)

Performed on a single 3T system and sequences will be acquired in a single sitting with an exam time under 45 minutes.

After a 50-minute uptake period, the patient will be positioned on the scanner bed with instructions to remain motionless. Injection of 10 mCi of 18F-Florbetapir (target dose 370 MBq, range 296 - 444 MBq) given. A helical CT image will be obtained at 50 minutes after injection of 18F-Florbetapir, followed by a 20-minute PET acquisition consisting of four 5-minute dynamic frames.

Intravenous bolus injection of approximately 370 MBq (10 mCi) of 18F- AV-1451 (approved under IND 124449). PET/CT image acquisition will include a low dose CT and then a 20-minute PET acquisition starting at 50-60 minutes after injection of 18F-T807 and will be performed as 4, 5-minute frames that will then be summed into one static frame. Serial frames will allow for adjustment in the case of patient motion.

A comprehensive battery of standardized neuropsychological tests administered by trained personnel.