1. Endoscopy Unit. Gastroenterology Department. ICMDiM. Hospital Clínic of Barcelona. University of Barcelona, Barcelona, Catalonia, Spain
2. Computer Science Department. Autonomous University of Barcelona and Computer Vision Center, Barcelona, Catalonia, Spain
3. IDIBAPS, Barcelona, Catalonia, Spain
4. CIBEREHD, Spain
5. Pathology Department. Hospital Clínic of Barcelona. University of Barcelona, Barcelona, Catalonia, Spain