1. Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan.
2. Department of Radiological Technology, Faculty of Health Sciences, Hokkaido University of Science, Sapporo, Japan.
3. Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
4. Department of Biofunctional Imaging, Fukushima Medical University, Fukushima, Japan.
5. Institute of Cyclotron and Drug Discovery Research, Southern TOHOKU Research Institute for Neuroscience, Koriyama, Japan.