Background: Endoscopic sphincterotomy (EST) is now a standard procedure for common bile duct stones. It is less invasive than surgical treatment and is well established, but complications such as bleeding and perforation occasionally occur. We have been investigating the safest and most useful method of preserving the papilla of Vater. In the present study we evaluated the effectiveness and safety of extracorporeal shock wave lithotripsy (ESWL) for common bile duct stones without preliminary EST.
Methods: From May 1992 to May 1995 ESWL was performed on 52 patients with common bile duct stones at our hospital. In all 52 patients a nasobiliary tube was inserted endoscopically, without preliminary EST, and ESWL was performed.
Results: Fragmentation and subsequent complete clearance of stones was achieved in 35 patients (67.3%), and no additional treatment was necessary. In 17 patients (25.0%) fragmentation was not achieved, so EST and endoscopic extraction were performed, and the stones were cleared completely. None of the patients had major complications with clinical sequelae. We compared the completely cleared group and the failed group, to assess the influence of various factors. Our findings indicated that smaller, 'floating' stones responded more favorably to ESWL. When the largest stone was < 15 mm in diameter and the stone index (diameter of common bile duct/diameter of stone) was > 1.0, the success rate was very high 25 of 27 = 92.6%).
Conclusions: This treatment offers several advantages because it is less invasive, has few complications, and can preserve the papilla of Vater. This method is especially suitable for patients with smaller, floating stones.