What causes occlusion of biliary duct?

► From gallstones closing the duct and this usually comes with severe acute pain, nausea, fever, and vomiting with no bile in vomit ? think angiocholitis, there’s something obstructing the liver ducts. ► Chronic abdominal pain with weight loss and vomiting without bile in vomiting ? think periampullary tumor, tumor obstructing the common bile duct or the pancreatic duct