1 Department of Medicine 1, Interdisciplinary Endoscopy, University of Erlangen-Nuremberg, Erlangen, Germany; Basil Hirschowitz Endoscopic Center of Excellence, Division of Gastroenterology and Hepatology, University of Alabama at Birmingham, Birmingham, Alabama, USA.
2 Basil Hirschowitz Endoscopic Center of Excellence, Division of Gastroenterology and Hepatology, University of Alabama at Birmingham, Birmingham, Alabama, USA.