1. Faculty of Graduate School of Biomedical Sciences and Engineering, Hokkaido University, Hokkaido 061‑0293, Japan
2. Department of Radiation Science, Graduate School of Health Sciences, Hirosaki University, Aomori 036‑8564, Japan
3. Department of Radiology and Radiation Oncology, Graduate School of Medicine, Hirosaki University, Aomori 036‑8562, Japan
4. Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Hirosaki University, Aomori 036‑8562, Japan