Abstract for presentation at 38th Annual Scientific Meeting of the Australian and New Zealand Society of Nuclear Medicine 2008

Radiation Dosimetry of the Amyloid Imaging Agent 18F-BAY94-9172 in Humans

  • Mr Timothy Saunder, Centre for P.E.T., Austin Health, Australia
  • Ms Kunthi Pathmaraj, Centre for P.E.T., Austin Health, Australia
  • Henri Tochon-Danguy, Centre for P.E.T., Austin Health, Australia
  • Victor Villemagne, Centre for P.E.T., Austin Health, Australia
  • Prof Christopher Rowe, Centre for P.E.T., Austin Health, Australia
  • T Dyrks, Bayer Schering Pharma AG, Germany
  • G Holl, Bayer Schering Pharma AG, Germany
  • Dr Graeme O'Keefe, Centre for P.E.T., Austin Health, Australia

    • Objectives:A-beta imaging has permitted new insights into Alzheimer's disease. The purpose of this study was to determine the radiation dosimetry of the novel amyloid tracer 18F-BAY94-9172(AV1/ZK) in humans.
    Methods:Three subjects (2 males,1 female,mean age 66.3yrs) were injected with 18F-BAY94-9172 (mean dose 319MBq) and scanned on a Philips Gemini PET/CT camera. Sequential wholebody PET images, consisting of 5 time points, were acquired over three hours.
    Organs of interest were defined from the CT scan and applied as Volume-Of-Interest to the wholebody PET image data from which the activity concentrations for the organs at each time point were determined. Organs considered as source organs were brain,lung,liver,kidney,spleen,gall-bladder contents,bladder contents,lower and upper large-intestine,small-intestine and vertebra. The activity concentrations for each organ were then scaled using the Standard Man values for organs. Bi-exponential curves were fitted to the individual Time-Activity-Curves from which the cumulated activity was determined. Gall-bladder contents was calculated as AUC plus physical decay after the final time point. Urinary-bladder contents were calculated with a Voiding Bladder Model with a voiding interval of 2.4 hrs. The cumulated-activities were then used with OLINDA to calculate the effective doses.
    Results:Organs with the highest effective doses were the ovaries, red-marrow,liver,LLI-wall and stomach wall with 2.74+/-0.17, 2.27+/-0.51, 1.96+/-0.,41, 1.89+/-0.08 and 1.58+/-0.13uSv/MBq respectively. The highest radiation absorbed doses received were gall-bladder wall,liver and urinary-bladder wall with 132.40+/-43.40, 39.07+/-8.31 and 24.77+/-7.36uGy/MBq respectively. A wholebody mean effective dose of 14.67+/-1.39uSv/MBq was calculated.
    Conclusions:The radiation dosimetry of 18F-BAY94-9172 is suitable for human use and is similar to other 18F-labelled radio-pharmaceuticals.

    Conference Organiser - ICMS Pty Ltd