Shotaro Tsunoda

Biliary drainage after hepaticojejunostomy can be challenging, particularly when recurrent tumor results in isolation of segmental intrahepatic bile ducts. Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) has been increasingly used as an alternative drainage approach in such patients.[1] [2] However, the antegrade deployment of multiple stents through endosonographically created routes (ESCRs) has not been standardized.[3] [4] [5] A 60-year-old man who had undergone right hepatectomy with hepaticojejunostomy for bile duct cancer was admitted with cholangitis due to a hepaticojejunostomy stricture ([Fig. 1]). EUS-HGS was initially performed via B2, and a 7-Fr dedicated plastic stent was placed. Because cholangitis subsequently developed in the isolated B3, an additional EUS-HGS was performed; however, recurrent cholangitis persisted. Biopsy from the B2 ESCR revealed adenocarcinoma, confirming local recurrence ([Fig. 2]). To control refractory cholangitis and allow systemic chemotherapy, antegrade partial stent-in-stent deployment via dual ESCRs was attempted ([Fig. 3]). First, a landmark guidewire was advanced alongside the B2 plastic stent into the jejunal limb and left in place. After reinsertion of the duodenoscope, a guidewire was placed alongside the B3 plastic stent. An 8-mm, 8-cm uncovered self-expandable metal stent (Niti-S Large Cell SR Slim Delivery, Taewoong Medical, Seoul, Korea) was deployed in an antegrade manner from B3 to the jejunal limb. A 7-Fr plastic stent (Through & Pass Type IT, Gadelius Medical, Tokyo, Japan) was placed in the B3 ESCR. The guidewire was then introduced through the B2 ESCR alongside the landmark guidewire and advanced through a mesh cell of the first metal stent. A second identical uncovered metal stent was then deployed in a partial stent-in-stent fashion. Finally, a 7-Fr plastic stent was left in the B2 ESCR ([Fig. 4], [Video 1]). Transient fever resolved conservatively, and systemic chemotherapy was initiated. Video 1 Antegrade partial stent-in-stent deployment is performed through dual ESCRs for disconnected B2 and B3 ducts after right hepatectomy with hepaticojejunostomy. To the best of our knowledge, this is the first report of antegrade partial stent-in-stent deployment through dual ESCRs for disconnected B2 and B3 ducts after right hepatectomy with hepaticojejunostomy. Endoscopy_UCTN_Code_TTT_1AS_2AH Received: 05 May 2026 Accepted after revision: 26 May 2026 Article published online: 12 June 2026 © 2026. 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

Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) using a 22-gauge needle and a 0.018-inch guidewire is well suited for bile duct puncture and initial guidewire insertion [1] [2]; however, subsequent tract dilation and stent delivery remain technically challenging. Although dilation devices compatible with a 0.018-inch guidewire have been reported [3] [4], tract dilation carries a potential risk of bile leakage. Furthermore, because no catheter specifically designed for a 0.018-inch guidewire has been available, switching to a stiff guidewire generally requires multiple device exchanges. This additional step may prolong the procedure and increase the risk of bile leakage [5]. A novel uneven double-lumen cannula (UDLC; PIOLAX, Tokyo, Japan) features an ultra-tapered tip designed for a 0.018-inch guidewire and a side lumen for a 0.035-inch guidewire, with a maximum diameter of 6-Fr ([Fig. 1]). This design enables effective bile aspiration while allowing one-step insertion of an additional stiff guidewire without device exchange, thereby improving procedural safety and stability while minimizing tract dilation. In the present case of EUS-HGS performed in a patient with hilar biliary obstruction and previously placed fully covered multi-hole metallic stents ([Fig. 2] and [Fig. 3]), a 0.018-inch guidewire (J-wire Premier Non-marker, J-Mit Co., Ltd, Kyoto, Japan) could not be advanced across the stents. Because of the short insertion length, a 0.018-inch guidewire alone was insufficient to provide adequate stability for stent delivery. Consequently, the novel UDLC was inserted over the 0.018-inch guidewire, enabling bile aspiration followed by insertion of an additional 0.035-inch stiff guidewire. Finally, a dedicated plastic stent (7-Fr, 10 cm, Through & Pass Type IT, Gadelius Medical, Tokyo, Japan) was successfully deployed without additional tract dilation ([Fig. 4]; [Video 1]). To the best of our knowledge, this is the first report of EUS-HGS using the novel UDLC designed for a 0.018-inch guidewire. This device addresses the limitation associated with 22-gauge needle access during EUS-HGS. Endoscopy_UCTN_Code_TTT_1AR_2AZ Endoscopy_UCTN_Code_CCL_1AZ_2AC Article published online: 13 February 2026 © 2026. 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

Antegrade laser lithotripsy via endoscopic ultrasonography-guided hepaticogastrostomy (EUS-HGS) is challenging when the intrahepatic bile duct forms acute angulation [1] [2]. A novel slim cholangioscope (9-Fr eyeMAX; Micro-Tech, Nanjing, China), featuring a highly flexible deflection system, has recently become available [3] [4] [5]. A 78-year-old man who had undergone pancreatoduodenectomy for a neuroendocrine tumor was admitted with a large intrahepatic biliary stone ([Fig. 1]). First, balloon enteroscopy-assisted endoscopic retrograde cholangiography was performed; however, severe adhesive angulation of the afferent limb resulted in poor maneuverability of the balloon enteroscope. Although the 9-Fr eyeMAX could be advanced with difficulty, targeting the intrahepatic stone by laser probe (LithoEVO; EDAP TMS, Lyon, France) was impossible ([Fig. 2]). Therefore, EUS-HGS was planned to create the antegrade route for stone removal. A non-dilated bile duct, identified posterior to a hepatic cyst, was punctured with 22-gauge needle. After guidewire placement toward the hilum, a double-pigtail plastic stent was deployed ([Fig. 3]). Three weeks later, the plastic stent was exchanged for a partially covered metallic stent, and antegrade stone removal was performed. The 9-Fr eyeMAX was inserted through the metallic stent; however, targeting the intrahepatic stone was difficult because of the acute intraductal angulation. Rotation of the cholangioscope and bile aspiration brought the stone into direct frontal view. Although the laser probe tip intermittently went out of view, the green aiming beam allowed clear discrimination between the stone and the bile duct wall. After laser lithotripsy, the hepaticojejunostomy anastomosis was dilated with a balloon catheter, and the fragmented stones were successfully removed. No residual stones were seen on cholangioscopy, and the metallic stent was removed ([Fig. 4]). The patient was discharged without complications. To the best of our knowledge, this is the first report of antegrade laser lithotripsy for intrahepatic biliary stones using a novel slim cholangioscope ([Video 1]). Endoscopy_UCTN_Code_TTT_1AR_2AH Article published online: 02 October 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

The utility of 22-gauge needle for endoscopic ultrasonography-guided hepaticogastrostomy (EUS-HGS) has been reported; however, a dedicated guidewire has not been developed [1] [2] [3] [4] [5]. Recently, a novel 0.018-inch guidewire (J-wire NM; J-MIT) without markers was developed to prevent guidewire stacking and a stiff shaft for smooth stent delivery. Additionally, a 7-Fr slim-delivery metallic stent (Niti-S EUS-BD system End Bare Single Flare; Taewoong Medical Co., Ltd.) has an ultra-tapered tip designed to minimize the gap with a 0.018-inch guidewire ([Fig. 1]). Herein, we report a case in which EUS-HGS was successfully performed using a novel 0.018-inch guidewire and slim-delivery metallic stent ([Video 1]). A 64-year-old man who had previously undergone distal gastrectomy with Roux-en Y reconstruction for advanced gastric cancer was admitted to our hospital due to obstructive jaundice caused by a recurrent tumor ([Fig. 2]). As balloon enteroscopy could not reach the papilla of Vater due to tumor infiltration ([Fig. 3]), EUS-HGS was attempted. The slightly dilated B3 was punctured using a 22-gauge needle (Expect Slim-line; Boston Scientific Co.) ([Fig. 4]). After the cholangiography, the novel 0.018-inch guidewire migrated outside of the bile duct; however, it was safely removed without guidewire stacking. After re-puncture, the guidewire was successfully inserted into the bile duct. Subsequently, tract dilation was performed using a 7-Fr bougie dilator dedicated to a 0.018-inch guidewire (ES Dilator Soft; Zeon Medical, Inc.). To minimize the risk of bile leakage, the novel metallic stent (8-mm, 12-cm) with a 7-Fr slim delivery system was inserted without guidewire exchange. The metallic stent was successfully placed from the bile duct to the stomach. The patient was discharged without adverse events following the improvement of jaundice. To the best of our knowledge, this is the first report of EUS-HGS using a novel 0.018-inch guidewire and an ultra-tapered, slim-delivery metallic stent. Endoscopy_UCTN_Code_TTT_1AS_2AH Article published online: 18 June 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

Several techniques for endoscopic ultrasonography-guided choledochoduodenostomy (EUS-CDS) without tract dilation have been reported to reduce the risk of bile leakage [1] [2] [3] [4]. However, bile leakage may still occur, particularly when the insertion of the stent delivery system is challenging. A novel self-expandable metallic stent (SEMS) with a 7-Fr slim delivery system (Niti-S EUS-BD system End Bare Single Flare; Taewoong Medical Co., Ltd., Gimpo, South Korea) features an ultra-tapered tip designed for use with a 0.025-in guidewire ([Fig. 1]). Its cross-wire structure provides a high radial force that minimizes the risk of stent migration. Herein, we present a case of EUS-CDS performed without tract dilation using this novel SEMS ([Video 1]). A 64-year-old woman with unresectable pancreatic cancer complicated by biliary obstruction was admitted to our hospital. Computed tomography revealed multiple metastases in the left liver lobe ([Fig. 2]). Initial transpapillary biliary drainage was attempted, but the guidewire could not be passed through the stricture. EUS-CDS was subsequently performed. A dilated common bile duct was punctured using a 19-gauge Franseen needle (TopGain; Medi-Globe GmbH, Grassau, Germany), and a 0.035-in guidewire was introduced. An attempt was made to insert a fully covered SEMS with an 8-Fr delivery system, but the tip of the system was unable to pass through the bile duct wall. A tapered catheter was then inserted, and the guidewire was exchanged for a 0.025-in version (VisiGlide 2; Olympus Medical Systems, Tokyo, Japan). Utilizing the ultra-tapered tip and the 7-Fr slim delivery system, the novel SEMS (8-mm diameter, 10-cm length) was advanced smoothly into the bile duct without the need for tract dilation. The stent was successfully deployed from the left hepatic duct to the duodenum ([Fig. 3]). The patient recovered uneventfully and was discharged without adverse events. To the best of our knowledge, this is the first reported case of EUS-CDS performed without tract dilation using a novel SEMS with an ultra-tapered slim delivery system. This simple approach offers a safe technique for EUS-CDS. Endoscopy_UCTN_Code_TTT_1AS_2AD Article published online: 18 June 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