1. Department of Endoscopy and Gastroenterology, Centre Hospitalier Universitaire Pontchaillou, Rennes, France
2. Department of Endoscopy and Gastroenterology, Centre Hospitalier Universitaire Dupuytren, Limoges, France
3. Department of Endoscopy and Hepatogastroenterology, Pavillon L, Edouard Herriot Hospital, Lyon, Francee