1. Department of Endoscopy, Santa Casa de Caridade Hospital, Bagé, RS, Brazil
2. Department of Endoscopy, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
3. Department of Gastroenterology and Endoscopy, Mãe de Deus Hospital, Porto Alegre, RS, Brazil
4. Department of Gastroenterology and Endoscopy, Santa Casa Hospital, Porto Alegre, RS, Brazil