1. Digestive Endoscopy Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
2. Center for Endoscopic Research Therapeutics and Training (CERTT), Università Cattolica del Sacro Cuore di Roma, Rome, Italy
3. Digestive Endoscopy Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Largo A. Gemelli, 8 00168 Rome, Italy