Cystic dilation of the extrahepatic bile ducts is rarely encountered d
uring elective biliary surgery planned for different indications, We r
eport here on a patient with unremarkable preoperative workup and norm
al intraoperative anatomy of the cystic pedicle in whom a type I chole
dochal cyst containing a large stone was detected by the combined use
of laparoscopic contact ultrasonography and intraoperative cholangiogr
aphy. This case report highlights the importance of intraoperative ima
ging modalities of the ductal system not only in preventing iatrogenic
injuries and their related complications, but also in detecting unsus
pected associated biliary pathology which might significantly change t
he course of surgical intervention.