1. Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
2. Department of Therapeutic Oncology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
3. Department of Medical Equipment, Kyoto University Hospital, Kyoto, Japan
4. Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan