This is a multi-center randomized controlled trial comparing extracorporeal shock-wave lithotripsy (ESWL) with per-oral pancreatoscopy-guided lithotripsy (PPL) in the treatment of patients with chronic pancreatitis and refractory main pancreatic duct stones. This study will be comparing the two treatment options for patients who have stones that fail initial endoscopic therapy via endoscopic retrograde pancreatography (ERCP). The study will look at the stone clearance rates and patient-centered outcomes including quality of life and pain.

Patients with chronic pancreatitis frequently develop obstructing pancreatic duct stones which can lead to severe pain. Current standard methods to remove these stones include ERCP and extracorporeal shock-wave lithotripsy (ESWL) which are limited in removing larger and multiple impacted stones. Availability in the USA of ESWL for this indication also may be limited even at major referral centers. The introduction of single-operator per-oral pancreatoscopy (SpyGlassTM) has enabled direct intraductal visualization to target stones. Retrospective studies demonstrate a high success rate but literature is quite limited, uncontrolled, and highly selective. Further, many experts and recent European Society Guidelines suggest that ESWL is the only primary therapy for larger stones (5mm or larger) and that intraductal endoscopy and lithotripsy should only be used for 'salvage' therapy in select patients.

A critical need exists to compare the efficacy of per oral pancreatoscopy-guided lithotripsy (PPL) with ESWL to determine which therapy is most efficacious in removing refractory PD stones. The investigators believe ERCP with POP has distinct advantages of localizing 'shocks' to the stones, helping to identify and treat underlying strictures in the duct, and lithotripsy of multiple stones can be performed at a single session with a recent multi-center international retrospective study showing all stones removed in a single session in over 70% of cases. Therefore, this project seeks to change the perceived standard of care as it relates to symptomatic pancreatic duct stones in this population, shifting the pendulum towards endoscopic and specifically pancreatoscopy-guided therapy.

Inclusion Criteria:

1. Subjects aged 18-89
2. Subjects with abdominal pain secondary to chronic calcific pancreatitis and main pancreatic duct stones found on cross-sectional imaging, EUS, or ERP with upstream PD dilation
3. Main PD stones in the head or body that are greater than 50% in size of the immediate downstream diameter of the pancreatic duct
4. Stones ≥ 5 mm in diameter or impacted in the main PD on cross-sectional imaging or EUS

Exclusion Criteria:

1. Subjects who have previously received PPL or ESWL for PD stones within 12 months of enrollment
2. Patients with PD stones isolated in the tail or side branches of the main duct
3. Pancreatic tail stones comprising more than one-third of the stone burden within the main PD, if multiple locations of stones are noted within the main PD
4. Nontraversable ansa loop with upstream stones
5. Inability to place a transpapillary pancreatic duct stent during ERP
6. Patients with prior pancreatic surgery or surgically altered gastroduodenal anatomy, such as Roux-en-Y surgery
7. Acquired pancreas divisum
8. Significant cardiopulmonary co-morbidities precluding general anesthesia
9. Patients with coagulation disorders that cannot be corrected to an INR below 2.0
10. Patients with ongoing alcohol abuse and/or illicit drug use, except products containing THC
11. Pregnancy
12. Patients in active treatment for malignancy other than non-melanoma skin cancer or papillary thyroid cancer

Deidentified data will be available to researchers

The data will become available at the conclusion of the study once the results are published.

Formal proposal required

The investigator interpreting final stone clearance pancreatograms will be blinded to the intervention received.