1. Gastroenterology & Endoscopy Unit, Fondazione Istituto Gemelli-G. Giglio, Contrada Pietra Pollastra Pisciotto, 90015 Cefalù, Italy
2. Department of Gastroenterology and Gastrointestinal Endoscopy, San Raffaele Hospital, 20132 Milan, Italy
3. Radiology Unit, Fondazione Istituto Gemelli-G. Giglio, Contrada Pietra Pollastra Pisciotto, 90015 Cefalù, Italy
4. Gastroenterology and Endoscopy Unit, S. Elia-Raimondi Hospital, 93100 Caltanissetta, Italy