Complete extraction of main pancreatic duct residual and microstones using an 8-wire basket catheter

Abstract

Extracorporeal shock wave lithotripsy (ESWL), pancreatoscopy-guided electrohydraulic lithotripsy (EHL), and endoscopic retrograde cholangiopancreatography (ERCP) are primary treatments for symptomatic main pancreatic duct (MPD) stones. However, incomplete clearance of residual/microstones post-treatment may cause symptom recurrence. We hypothesized that the 8-wire biliary basket catheter could be suitable for MPD stone extraction and aimed to analyze its ability to achieve more complete clearance of MPD residual/microstones. Patients suspected to have MPD residual/microstones ≤5 mm because of abdominal symptoms, computed-tomography examination results, and pancreatography results after previous therapy, including ERCP, EHL, and ESWL, were retrospectively enrolled. Patients with severe MPD stenosis/biliary obstruction requiring ERCP drainage were excluded. Extraction of residual/microstones was attempted using an 8-wire basket that is widely expandable in the narrow pancreatic duct and can capture and sweep stones in the narrow pancreatic duct. Technical success was defined as the extraction of residual/microstones. The primary outcome was the technical success rate. Secondary outcomes were therapeutic details of stone extraction using the 8-wire basket catheter, including symptom improvements. The technical success rate was 100% for seven patients; 1–8 residual/microstones were extracted. An improvement was observed in five patients with symptoms after the previous therapy. Three patients underwent residual stone extraction after extraction using a dedicated basket. No patient experienced symptom recurrence during the 270-day follow-up period. The 8-wire basket resulted in successful MPD residual/microstone extraction and pancreatic symptom improvement. This method may prevent symptom recurrence caused by incomplete residual/microstone clearance.