Therapeutic utility of SpyDS-guided electrohydraulic lithotripsy in treatment of intrahepatic bile duct stones: a retrospective single-center study

Background Recently, the availability of the SpyGlass DS Direct Visualization system (SpyDS) has introduced a new era in digital peroral cholangioscopy (POCS). Numerous studies have highlighted its significant advantages over the conventional SpyGlass system, enabling diverse therapeutic interventions. Therefore, this retrospective study aimed to comprehensively assess the clinical utility and safety of SpyDS-guided electrohydraulic lithotripsy (EHL) for managing intrahepatic bile duct stones (IBDS) that are not amenable to conventional endoscopic therapy. Methods In this retrospective single-center study, consecutive patients with IBDS who underwent SpyDS-guided EHL were enrolled between June 2022 and July 2025. The clinical utility of this endoscopic surgical approach was determined by the technical success rate, stone clearance rate, postoperative hospital stay, and imaging evidence before and after the operation. The incidence of adverse events and associated outcomes were thoroughly evaluated to ensure clinical safety. Results Forty-five patients (21 men, 24 women; mean age 52.9 years) with a median stone length 2 cm underwent SpyDS-guided EHL. The overall technical success rate was 88.9%, while the overall clinical success rate was 86.7%. Complete biliary stone clearance was achieved in the first session for 76.9% of patients (30/39), with only nine patients (23.1%) requiring an additional endoscopic session. The proportion of stones located in the right posterior segmental bile duct in the clinical non-success group (5/6, 83.3%) was significantly higher than that in the clinical success group (0/39, 0%), with a statistically significant difference (P < 0.001). The median total procedure time for complete stone removal was 70 minutes, and the median duration of SpyDS procedure was 29 minutes. Complication rates were observed in a total of 35.6% cases, including cholangitis in eight patients, hyperamylasemia in five patients, and abdominal pain in three patients - all resolved through conservative management without any serious complications such as hemorrhage or perforation. Conclusions SpyDS-guided EHL demonstrates promising outcomes in the management of intrahepatic calculi, showcasing its feasibility, efficacy, and safety as a potential alternative therapeutic approach for this condition. However, its applicability may be limited to non-right posterior bile duct stones.