2012e-457 2017b-357 atlases bariatricsurgery bileductdiseases bileducts contrastmedia digestivesystemsurgicalprocedures diseases disorders gastroenterology internalmedicine liver liverdiseases liverneoplasms malabsorptionsyndromes medicalradiology medicine metabolicdiseases metabolism methods morbid morbidobesity obesity oncology pancreas pancreaticdiseases pathology pathophysiology r895-920 reoperation surgery ultrasonography