Pigtail stents: an alternative in the treatment of difficult bile duct stones

When bile duct stones cannot be removed after sphincterotomy by balloon or basket extraction, stent placement can serve as a bridge to additional procedures. Biliary stents may also fragment large stones, allowing them to pass spontaneously or making them easier to extract at a later time.

Twenty patients with difficult to extract bile duct stones were prospectively studied. The patients underwent ERCP and placement of a 7F double-pigtail stent in the bile duct for 6 months.

In seven patients (35%), repeat ERCP revealed no stones in the duct. Four patients (20%) had small stone fragments that were easily extracted with a balloon. Six patients (30%) continued to have large stones at repeat ERCP; two of these patients eventually underwent surgery, the duct was cleared in three with mechanical lithotripsy, and one had long-term stenting. Three patients (15%) did not undergo repeat ERCP and were therefore treated with long-term stent placement.

This study suggests that placement of a pigtail biliary stent is a safe and effective alternative in the management of bile duct stones that resist extraction if lithotripsy is not available. After 6 months of stent placement, stones may pass or become easier to remove in a significant proportion of patients.