Bile Duct Injury or Stricture: Given the patient's history of cholecystectomy and the finding of physiologic prominence of the bile ducts on ultrasound, a bile duct injury or stricture is a plausible cause for unrelieved abdominal pain. This condition can lead to obstruction of bile flow, causing pain.

Residual or Recurrent Gallstones: Although the patient has undergone cholecystectomy, it's possible for gallstones to remain in the bile ducts (choledocholithiasis) or to form de novo, leading to obstruction and pain.
Biliary Dyskinesia: This condition, characterized by abnormal contraction of the sphincter of Oddi, can cause abdominal pain similar to that experienced before cholecystectomy.
Adhesions or Bowel Obstruction: Post-surgical adhesions can lead to bowel obstruction, which may present with abdominal pain, nausea, vomiting, and constipation.

Hemorrhage or Hematoma: Post-operative bleeding can occur and may not always be immediately apparent. It's crucial to consider this diagnosis due to its potential for severe consequences.
Perforation of a Viscus: Although less common, any surgical procedure carries the risk of accidental perforation of adjacent organs, which can lead to peritonitis and severe infection.
Pancreatitis: Inflammation of the pancreas can be triggered by various factors, including surgical manipulation during cholecystectomy. It's a condition that requires prompt recognition and treatment.

Sphincter of Oddi Dysfunction Type III: This condition involves abdominal pain related to the sphincter of Oddi but without evidence of obstruction. It's less common and can be challenging to diagnose.
Biliary Ascariasis: In endemic areas, parasitic infection of the biliary tree by Ascaris lumbricoides can cause obstruction and pain.
Mirizzi Syndrome: A rare condition where a gallstone becomes impacted in the cystic duct, causing compression of the common bile duct and potentially leading to obstructive jaundice and pain.