1. Department of Gastrointestinal Surgery ; Tokyo Medical and Dental University; Tokyo Japan
2. Department of Maxillofacial Surgery; Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University; Tokyo Japan
3. Department of Oral & Maxillofacial Surgery ; Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University; Tokyo Japan
4. Department of Surgery ; Soka Municipal Hospital; Saitama Japan