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What is A 70-year-old male underwent a choledochoduodenostomy for multiple common duct stones. The patient now presents with RUQ abdominal pain. What should be the initial test (least invasive with the best yield) to determine patency of the choledochoduodenostomy? and explain in detail?
A HIDA scan will show excretion of the radiolabeled isotope into the biliary tree, but there will be no flow into the duodenum, indicating that the biliary-enteric anastomosis is occluded. If an upper GI study with barium is performed, visualization of the common bile duct would indicate patency of the choledochoduodenal anastomosis.