Removal of lollipop-shaped stent-stone complex using direct-vision laser lithotripsy

This is the authors' abstract. We don't add key points for this paper.

Long-term retention of biliary plastic stents (PS) can lead to a rare complication: the formation of a lollipop-shaped stent-stone complex (LSSC) [ 1 ], where stones encase the proximal end of the stent, making endoscopic removal technically difficult. We report a case of successful LSSC removal using peroral cholangioscopy (POCS)-guided frequency-doubled dual pulse Nd:YAG (FREDDY) laser lithotripsy. A 72-year-old man, previously diagnosed with IgG4-related sclerosing cholangitis, underwent biliary and pancreatic PS placement three years prior to alleviate obstructive jaundice ([ Fig. 1 ]), followed by corticosteroid therapy. He was lost to follow-up. One month before admission, he presented with jaundice and fever. Emergency ERCP showed resolution of the biliary stricture but revealed a retained LSSC in the common bile duct (CBD). Removal attempts using standard tools failed, fracturing the stent at the duodenal lumen. A supplementary PS was placed to ensure drainage ([ Fig. 2 ]). Following stabilization, repeat ERCP was performed using POCS-guided laser lithotripsy. The PS was fully encased in yellow stones, forming an LSSC. FREDDY laser lithotripsy (U-100 Plus; World of Medicine, Berlin, Germany) was applied at the stent-stone interface under direct visualization to fragment the stones and gradually release the stent. The stent was successfully removed, and residual stones were cleared ([ Fig. 3 ], [ Video 1 ]). The patient recovered well and was discharged three days later. Fig. 1 Initial ERCP findings (3 y prior). a Cholangiography showed a smooth, symmetrical stricture in the pancreatic segment of the common bile duct with upstream dilation. b Pancreatography revealed a slender, smooth stricture in the pancreatic head region of the main pancreatic duct, with mild dilation in the body and tail. c Plastic stents were placed in both the bile and pancreatic ducts. Fig. 2 Emergency ERCP findings (1 mo prior). a Biliary and pancreatic plastic stents were seen in situ, with cast-like pancreatic duct stones along the pancreatic stent. b Cholangiography revealed a round filling defect encasing the stent, forming a lollipop-shaped stent-stone complex. c A second biliary stent was placed alongside the original. Fig. 3 POCS-guided laser lithotripsy for LSSC removal. a POCS visualized a blue plastic stent encased in yellow stones, forming an LSSC. b, c A laser fiber was applied to the stent-stone interface and large stone. d Lithotripsy successfully fragmented the stone. e Cholangiography confirmed LSSC resolution and stone fragmentation. f Both stent and stone fragments were removed; balloon-occluded cholangiography showed no residual filling defects. LSSC formation is associated with long-term stent retention (≥301 days) and CBD dilation [ 2 ]. The potential for LSSC formation should be considered in patients with long-term PS indwelling and dilated CBD. Endoscopic LSSC removal is technically challenging: standard endoscopic tools may fail, and forcible extraction risks ductal injury and perforation. Extracorporeal shock wave lithotripsy is technically complex [ 3 ], while surgical intervention is traumatic. FREDDY laser lithotripsy is safer than Ho:YAG laser and electrohydraulic lithotripsy [ 4 ] [ 5 ]. POCS-guided FREDDY laser lithotripsy offers a safe, minimally invasive, and effective approach for LSSC management. Download Video Removal of lollipop-shaped stent-stone complex using direct-vision laser lithotripsy.Video 1 Endoscopy_UCTN_Code_CPL_1AK_2AF Endoscopy E-Videos https://eref.thieme.de/e-videos E-Videos is an open access online section of the journal Endoscopy , reporting on interesting cases and new techniques in gastroenterological endoscopy. All papers include a high-quality video and are published with a Creative Commons CC-BY license. Endoscopy E-Videos qualify for HINARI discounts and waivers and eligibility is automatically checked during the submission process. We grant 100% waivers to articles whose corresponding authors are based in Group A countries and 50% waivers to those who are based in Group B countries as classified by Research4Life (see: https://www.research4life.org/access/eligibility/ ). This section has its own submission website at https://mc.manuscriptcentral.com/e-videos . Publication History Article published online: 29 July 2025 © 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany