1. Koganei Tsurukame Clinic, Endoscopy Center, Tokyo, Japan
2. Shinjuku Tsurukame Clinic, Digestive Disease Center, Tokyo, Japan
3. Tokyo Medical and Dental University, Department of Gastroenterology and Hepatology, Tokyo, Japan
4. Mirraza Shinjuku Tsurukame Clinic, Tokyo, Japan
5. Yotsuya Medical Cube, Endoscopy Center, Tokyo, Japan