A novel approach to common bile duct stone extraction

Abstract

To the Editor: We recently found a snare with a mesh retrieval net useful for the endoscopic removal of bile duct stones. Our patient was a 72-year-old woman with dementia and end- stage renal disease who presented with lethargy, fever to 104° F, and pseudomonal sepsis. Her serum liver tests were normal except for a mildly elevated alkaline phosphatase level. An ultrasound revealed marked intrahepatic and common bile duct dilatation with multiple mobile stones, as well as gallbladder stones. ERCP showed a saccular, dilated bile duct over 2 cm in diameter with approximately 20 mobile faceted stones, each about 5 to 8 mm in diameter. With manipulations the stones floated around in the duct like guppies in a fishbowl. After sphincterotomy about 10 stones were retrieved, but the remainder could not be captured, floating away from an open Dormia basket or bobbing around a 15 mm retrieval balloon. A stent was placed. At repeat ERCP 2 weeks later a snare with a mesh retrieval net (Disposable Roth Retrieval Net, U.S. Endoscopy Group, Inc., Mentor, Ohio) was used to remove bile duct stones (Fig. 1). The snare was advanced into the bile duct beside a .035-inch guidewire, opened above the stones, and withdrawn from the duct. The opened net seined the duct, trapping stones with each pass. The stones were easily dropped in the duodenum (Figs. 2 and 3). Figure 2Cholangiogram of the netted snare (small arrow) in the CBD with an entrapped stone (open arrowhead).View Large Image Figure ViewerDownload Hi-res image Download (PPT)Eight stones were retrieved, but two small stones could not be captured and a stent was again placed. Figure 3Netted snare with captured stones.View Large Image Figure ViewerDownload Hi-res image Download (PPT)The patient did well after the procedure and did not develop any postprocedural complications, although she died (from unrelated causes) 6 weeks later. We found a netted snare useful for the entrapment and removal of stones in a markedly dilated common bile duct. The open net captured stones that bobbed away from other retrieval devices. This device was recently marketed for the endoscopic removal of polyps, excised tissue, and foreign bodies1Webb WA Management of foreign bodies of the upper gastrointestinal tract: update.Gastrointest Endosc. 1995; 41: 39-51Abstract Full Text Full Text PDF PubMed Scopus (462) Google Scholar, 2Waye JD How big is too big?.Gastrointest Endosc. 1996; 43: 256-257Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar and a similar device has been used for difficult ureteral stones.3Phan CN Stoller ML Ureteric retrieval net: comparison with stone extraction by dormia baskets in an in vitro porcine model.Br J Urol. 1994; 73: 33-36Crossref PubMed Scopus (4) Google Scholar Caution should be used with this technique, given the possibility of impacting a large stone at the ampulla, although a mechanical lithotripter could probably be passed over an entrapped snare to disrupt the retrieval net. Theoretically, this snare may be useful in retrieving fragments after lithotripsy. We think that a netted snare will be a seldom used but nonetheless welcome addition to the stone retrieval armamentarium.