Biokinetics and dosimetry of [18F]flutemetamol in patients with Alzheimer’s disease

Beta-amyloid positron emission tomography/computed tomography (PET/CT) with [18F]flutemetamol is used to demonstrate presence of Alzheimer's disease. With the possibility to use [18F]flutemetamol PET/CT for early detection of mild cognitive impairment and the development of prevention drugs, the demand for the procedure may increase significantly. The biokinetics and dosimetry of [18F]flutemetamol in 7 patients (62-73 y) were studied. Knee-to-head PET/CT scans were acquired 15 min, 1, 2, 3, 4, and 5 hours after intravenous injection of 185 MBq. Activity in blood samples and 20-hour urine was analyzed. Volumes of interest for organs with enhanced activity content were segmented in the PET-images. A biokinetic compartment model was created to derive time-activity data for different organs. Organ doses and effective dose were calculated using IDAC-Dose 2.1 in accordance with ICRP publication 103. The effective dose coefficient for [18F]flutemetamol was 21 μSv/MBq (4 mSv@185 MBq). The colon received highest absorbed dose, 17 mGy.