1. Division of Medical Radiation Hygiene, Institute of Radiation Hygiene, Federal Office for Radiation Protection, Neuherberg, Germany.
2. Research Program “Radiological Diagnostics and Therapy,” German Cancer Research Center (DKFZ), Heidelberg, Germany.
3. Department of Biomedical Engineering, University of Applied Sciences, Jena, Germany.
4. Department of Nuclear Medicine, University of Heidelberg, Heidelberg, Germany.