Kenichi Nakajima1, Hiroshi Wakabayashi2. 1. Department of Functional Imaging and Artificial Intelligence, Kanazawa University Graduate School of Medicine, 13-1 Takaramachi, Kanazawa, 920-8640, Japan. nakajima@med.kanazawa-u.ac.jp. 2. Department of Nuclear Medicine, Kanazawa University Hospital, Kanazawa, Japan.