A Pivoting Common Hepatic Duct Stone: Successful Removal of an Unexpected Nidus for Stone Formation using Spyglass

Abstract

Purpose: Most biliary stones originate from the gall bladder and are readily treated endoscopic retrograde cholangio-pancreatography (ERCP). We present successful treatment of a common hepatic duct (CHD) stone and removal of an unexpected foreign body (migrated sutures) by cholangioscopy. Case report: A 54 year old patient who had an open cholecystectomy 13 years ago for acute cholecystitis presented with a 3 week history of vague right side abdominal pain. Her aspartate transaminase was 116 IU, alanine transaminase was 121 IU, total bilirubin 1.8 mg/dl and alkaline phosphatase 1120 IU. At initial ERCP, a dilated bile duct was found with an “hour glass” stricture at the junction of the CHD and common bile duct (CBD). Several surgical clips were visualized in proximity to the CHD containing a large filling defect. Attempts at stone extraction and mechanical lithotripsy were unsuccessful. Peculiarly, the filling defect appeared to pivot on attempted extraction. A 10 french biliary stent was placed. After a failed second attempt at lithotripsy, cholangioscopy and electrohydraulic lithotripsy was performed using Spyglass (Boston Scientific, Natick, MA, USA). Despite fragmenting the stone using a power setting up to 60% and a frequency of 10, only partial removal of the stone could be accomplished. Stents were placed and she was brought back for a completion cholangioscopy with further lithotripsy if needed. During the procedure stone fragments and sludge in the distal CHD were easily be flushed out. Surprisingly, a tuft of sutures projected out from a focus in the CHD where the stone appeared to pivot. This was then grabbed using a SpyBite forceps and extracted by simple traction. On removal of this tuft, a continuous suture that took approximately five passes through the CBD was noted. This was partially removed, releasing the sutured walls of the CHD. The patient remains asymptomatic and with normal liver tests on follow up post procedure. Discussion: With the exception of migrated biliary stents, foreign bodies are uncommon in the biliary system. Surgical clips, pieces of t-tubes, and suture material have all been reported. Our patient had an open cholecystectomy, but no intervention on the CBD was reported. In retrospect we speculate that the surgeon while suturing took several bites through the CBD and the knot eroded/migrated into the duct providing an unusual nidus for developing a pivoting stone. We conclude that the presence a migrated foreign body, including migrated surgical hardware or sutures be considered in the differential for a secondary process in patients that present with bile duct stones after cholecystectomy. In such cases a cholangioscopy should be considered.