1. Department of Surgery and Anatomy, Faculty of Medicine of Ribeirão Preto, University of São Paulo (FMRP-USP), São Paulo 05508-220, Brazil
2. Postgraduate Program, Department of Surgery and Anatomy, Faculty of Medicine of Ribeirão Preto, University of São Paulo (FMRP-USP), São Paulo 05508-220, Brazil
3. University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo (FMRP-USP), São Paulo 05508-220, Brazil
4. Digestive Endoscopy Service, Hospital Moriah, São Paulo 04084-002, Brazil
5. Department of Diagnostic Imaging, Federal University of São Paulo, São Paulo 04021-001, Brazil