[1] Fdn Policlin Univ Agostino Gemelli IRCCS, Digest Endoscopy Unit, Rome, Italy
[2] Univ Cattolica Sacro Cuore, Ctr Endoscop Res Therapeut & Training CERTT, Milan, Italy
[3] Policlin Univ Paolo Giaccone, Sect Gastroenterol & Hepatol Promise, Palermo, Italy
[4] Yokohama City Univ Med Ctr, Div Endoscopy, Yokohama, Japan
[5] Univ Cattolica Sacro Cuore, Rome, Italy
[6] AUSL Romagna, Osped Morgagni Pierantoni, Gastroenterol & Digest Endoscopy Unit, Forli, Italy
[7] Yokohama City Univ, Dept Gastroenterol, Grad Sch Med, Yokohama, Japan