1. Digestive Endoscopy Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
2. Centre for Endoscopic Research Therapeutics and Training (CERTT), Università Cattolica del Sacro Cuore, Rome, Italy
3. Radiology Department, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy