Pancreatoscopy with Electrohydraulic Lithotripsy (EHL): Primary or Adjunctive Therapy for Pancreatic Stones?

Abstract

BACKGROUND: Pancreatic duct (PD) hypertension is a mechanism of pain in calcific chronic pancreatitis and the rationale for endotherapy. Extracorporeal shockwave lithotripsy (ESWL) is used to treat PD stones but requires ERCP for stone removal. Peroral pancreatoscopy (PP) and EHL has been used with ESWL but not as primary therapy. The objective of this study is to evaluate PP as sole therapy for PD stones. METHODS: Prospective study of consecutive patients (pts) undergoing PP for stone clearance were followed using a data collection instrument. Technical success was defined as complete stone clearance. Clinical improvement was defined as >50% reduction in pain or narcotic analgesia. RESULTS: Between 2/00 and 6/03, 15 pts (5M, 10F),mean age 55 yr (range 38-82) underwent 24 PP for PD stones. Etiologies: alcohol (11), idiopathic (2), other (2). All pts required narcotic analgesia and/or frequent hospitalizations for pain control. Pts had an average of 1.8 ERCP attempts (range 0-5) prior to PP; 1 pt had a failed ESWL elsewhere. PP was successful via the major papilla (n=10) or minor papilla (n=2) in 12/15 pts (80%) but failed to traverse the PD obstruction in the head of the pancreas in 3. Stones in the head or body of the PD were found in all 12 pts; 8/12 pts required EHL. Other techniques used for extraction of stones included mechanical lithotripsy, saline irrigation, basket and balloon sweeps. Technical success was achieved in 9/12 (75%) patients. Number of PP sessions to achieve complete stone clearance: one (n=4), two (n=3), three (n=2). Two patients had partial stone clearance and one had pain resolution after transmural pseudocyst drainage. Ten of 12 treated pts (83%) reported clinical improvement for a mean of 14.5 mos (range 2-22). Follow-up interventions for the 9 pts who had stone clearance: biliary bypass (n=1), Puestow procedure (n=1), recurrent stones (n=2) treated with repeat ERCP. Follow-up interventions for the other 6 pts: Puestow (n=1), biliary bypass (n=1) and celiac axis block (n=1) CONCLUSIONS: (1) As primary therapy, PP achieved stone clearance associated with a sustained clinical improvement in the majority of pts. (2) Randomized studies are needed to compare the cost-effectiveness of PP with EHL versus ESWL-ERCP or surgery.