Confluence Stones at the Junction of the Cystic Duct and an Aberrant Anterior Sectoral Bile Duct: A Case Report.

Abstract

Introduction: Confluence stones usually arise when gallstones impacted in the cystic duct migrate toward the biliary confluence. Surgical treatment can be technically demanding because of chronic inflammation and distorted anatomy. Confluence stones at the junction between the cystic duct and an aberrant bile duct are extremely rare. We report a successfully treated case of confluence stones arising at the junction of the cystic duct and an aberrant anterior sectoral bile duct with a communicating accessory bile duct.

Case presentation: A 38-year-old woman presented with abdominal pain, and biliary stones were detected. Magnetic resonance cholangiopancreatography demonstrated an aberrant anterior sectoral bile duct draining independently into the common bile duct. Biliary stones were identified both within this duct and at its junction with the cystic duct. Endoscopic retrograde cholangiography confirmed the biliary anatomy and additionally revealed a communicating accessory bile duct between the anterior and posterior sectoral ducts. The stones within the distal portion of the aberrant duct were removed endoscopically, but the impacted confluence stones could not be extracted. Therefore, open surgery was performed. After exposure of the junction, the confluence stones were removed through a semicircumferential incision. Complete stone clearance was confirmed by intraoperative cholangioscopy and cholangiography. The patient was discharged on POD 11 with no bile leakage. At 14 months postoperatively, she remained asymptomatic and had experienced no episodes of cholangitis.

Conclusions: We report a rare case of confluence stones arising at the junction of the cystic duct and an aberrant anterior sectoral bile duct. Preoperative assessment of the drainage territory and intraoperative evaluation of the duct diameter, ischemia, and tissue fragility are essential for appropriate and safe repair of the bile duct defect. The repair strategy should not rely on presumed bypass flow through a communicating accessory bile duct because its functional capacity cannot be reliably predicted.