Comparing the Efficacy and Safety of Holmium Laser Lithotripsy Versus Electrohydraulic Lithotripsy for the Treatment of Difficult Choledocholithiasis and Pancreatic Duct Stones

This study aims to assess two main questions. 1: Whether low-wattage holmium:YAG laser lithotripsy (using the Quanta System Litho EVO device) is safe and effective in the management large and/or difficult bile duct or pancreatic duct stones. 2: Whether low-wattage holmium:YAG laser lithotripsy is non-inferior to electrohydraulic lithotripsy in the management of large and/or difficult gallstones.

Part one of the study will investigate whether utilizing the low-wattage holmium:YAG laser lithotripsy device via single-operator cholangioscopy (SOC-LL) is safe and effective to treat large and/or difficult choledocholithiasis or pancreaticolithiasis.

Part two of the study will be a non-inferiority study to determine if SOC-LL is non-inferior for stone clearance, among other secondary outcomes, compared to electrohydraulic lithotripsy via single-operator cholangioscopy (SOC-EHL).

Patients who meet the inclusion criteria will undergo ERCP procedures and will either undergo SOC-LL or SOC-EHL to treat their large and/or difficult choledocholithiasis or pancreaticolithiasis. Stone clearance and other procedural or safety measures will be assessed after the procedure. The patient will be monitored after the procedure for adverse events and the administration of medications or admission to the hospital will be determined by the proceduralist. Roughly 30 days after the procedure the patient will be called to assess for any adverse effects as well as to determine symptom resolution.

• Laser lithotripsy with low-wattage holmium laser (Device), also known as laser lithotripsy, lithotripsy: Use of low-wattage holmium laser for lithotripsy of large and/or difficult bile duct stones or pancreatic duct stones during ERCP.
• Electrohydraulic lithotripsy (Device), also known as EHL: Use of electrohydraulic lithotripsy for management of large and/or difficult bile duct or pancreatic duct stones.

Primary outcomes

• Complete stone clearance [Immediately after the procedure]: Complete stone clearance is defined as the lithotripsy and clearance of ductal stone fragments as confirmed on cholangiogram or pancreaticogram at the end of the index/first procedure of the study.

Secondary outcomes

• Overall complete stone clearance rate [Immediately after the final procedure]: This describes the rate of complete stone clearance at the end of the final procedure required to completely clear stones, regardless of the number of procedures required to do so.
• Number of procedures [Immediately after the final procedure]: Describes the number of ERCP procedures required to achieve complete stone clearance.
• Total procedure time [Immediately after the final procedure]: Total duration of index ERCP procedure. Will also document total procedural time for all necessary ERCPs to achieve stone clearance.
• Total lithotripsy time [Immediately after the final procedure]: Duration of the activation time for either the laser lithotripsy or the electrohydraulic lithotripsy devices during the study duration.
• Rate of rescue mechanical lithotripsy [Immediately after the final procedure]: Describes the percentage/rate of time that the patient requires rescue mechanical lithotripsy after failure of the primary modality (SOC-LL or SOC-EHL).
• Length of post-procedure hospital stay [Immediately after the final procedure]: Describes the amount of time in days the patient spent in the hospital after any and all required procedures to achieve complete stone clearance.

Sex: All, ages: 19 Years to 85 Years

Inclusion Criteria:

* Age 19-85 years
* Signed written informed consent.
* Presence of one or more biliary (common bile duct or intrahepatic) or pancreatic duct stones that are deemed "difficult" based on at least one of the following criteria:

  * Stone diameter ≥ 15 mm in any single dimension as measured on prior cross-sectional imaging (CT, MRCP, or EUS).
  * Presence of an impacted stone that cannot be dislodged with a standard balloon or basket.
  * Stone located proximal to a benign biliary or pancreatic duct stricture.
  * Documented failure of stone extraction during a prior ERCP attempt using standard techniques (e.g., sphincterotomy with balloon/basket extraction).

Exclusion Criteria:

* Pregnancy: Repeated ERCP would be delayed until after delivery if possible
* Clinically significant, uncorrectable coagulopathy (defined as INR > 1.5 or platelet count < 50,000/μL).
* Surgically altered upper gastrointestinal anatomy that precludes conventional ERCP access (e.g., Roux-en-Y gastric bypass), unless an alternative access route (e.g., laparoscopy-assisted or EUS-directed) is planned as the standard of care.
* Known or highly suspected malignant biliary or pancreatic stricture associated with the stone.
* Acute pancreatitis at the time of screening, unless it is gallstone pancreatitis with persistent biliary obstruction, for which ERCP is therapeutically indicated.
* Severe cardiopulmonary disease or other comorbidities that, in the judgment of the investigator, would make the patient an unsuitable candidate for a prolonged endoscopic procedure under general anesthesia.
* Known life expectancy of less than 6 months.
* Inability or unwillingness to comply with study procedures or follow-up requirements.

• ASGE Standards of Practice Committee; Buxbaum JL, Abbas Fehmi SM, Sultan S, Fishman DS, Qumseya BJ, Cortessis VK, Schilperoort H, Kysh L, Matsuoka L, Yachimski P, Agrawal D, Gurudu SR, Jamil LH, Jue TL, Khashab MA, Law JK, Lee JK, Naveed M, Sawhney MS, Thosani N, Yang J, Wani SB. ASGE guideline on the role of endoscopy in the evaluation and management of choledocholithiasis. Gastrointest Endosc. 2019 Jun;89(6):1075-1105.e15. doi: 10.1016/j.gie.2018.10.001. Epub 2019 Apr 9. PMID 30979521

• Neal A Mehta, MD, Principal investigator, Rush University Medical Center, Department of Digestive Diseases and Nutrition, Center for Interventional and Therapeutic Endoscopy