This patient underwent ultrasound 2 years prior to the CT, demonstrating findings consistent with choledocholithiasis or polyp in the common bile duct. Given the patient's advanced age (90) and lack of laboratory abnormalities, no further intervention was performed at that time.

The patient then presented with abdominal pain and transaminitis, which was improving at the time of imaging. On the CT, there is heterogeneous hepatic perfusion in the late arterial phase, which is likely related to resolving biliary obstruction/inflammation. The oval filling defect in the distal common bile duct with the same shape and dimension has finding on ultrasound can again be seen, and likely resulted in intermittent obstruction of the common bile duct.