Extracorporeal Shock Wave Lithotripsy for Prevention of Recurrent Pancreatitis Caused by Obstructive Pancreatic Stones

Objectives: Obstructive pancreatic duct stones can cause recurrent attacks of acute pancreatitis and chronic abdominal pain. Use of extracorporeal shock wave lithotripsy (ESWL) for treatment of abdominal pain associated with obstructive pancreatic duct stones has been well documented. However, its effect on prevention of recurrent pancreatitis in this group of patients has not been studied. Methods: Patients with recurrent episodes of acute pancreatitis due to obstructive pancreatic duct stones not amenable to endoscopic removal were prospectively examined. All patients underwent ESWL by a pancreatologist using an electromagnetic shock wave lithotripter. After ESWL, the patients were followed up for recurrence of acute pancreatitis. Results: Ten patients underwent 13 sessions of ESWL. Complete and partial ductal clearances were achieved in 7 and 3 patients, respectively. The mean length of follow-up was 20 months (range, 12-36 months). Three patients had recurrent attacks of acute pancreatitis during the follow-up period, caused by recurrence of obstructive stones in 2 and presence of main duct stricture in 1 patient. Conclusions: Extracorporeal shock wave lithotripsy of obstructive pancreatic duct stones in patients with recurrent attacks of acute pancreatitis can prevent further attacks. New episodes of acute pancreatitis in this group of patients may indicate stone recurrence or presence of strictures. Abbreviations: CT - computed tomography, ERCP - endoscopic retrograde cholangiopancreatography, ESWL - extracorporeal shock wave lithotripsy