Outcome of simple use of mechanical lithotripsy of difficult common bile duct stones

AIM: The usual bile duct stone may be removed by means of Dormia basket or balloon catheter, and results are quite good. However, the degree of difficulty is increased when stones are larger. Studies on the subject reported many cases where mechanical lithotripsy is combined with a second technique, e.g. electrohydraulic lithotripsy (EHL), where stones are crushed using baby-mother scope electric shock. The extracorporeal shock-wave lithotripsy (ESWL) or laser lithotripsy also yields an excellent success rate of greater than 90%. However, the equipment for these techniques are very expensive; hence we opted for the simple mechanical lithotripsy and evaluated its performance. METHODS: During the period from August 1996 to December 2002, Mackay Memorial Hospital treated 304 patients suffering from difficult bile duct stones (stone>1.5 cm or stones that could not be removed by the ordinary Dormia basket or balloon catheter). These patients underwent endoscopic papillotomy (EPT) procedure, and stones were removed by means of the Olympus BML-4Q lithotripsy. A follow-up was conducted on the post-treatment conditions and complications of the patients. RESULTS: Out of the 304 patients, bile duct stones were successfully removed from 272 patients, a success rate of about 90%. The procedure failed in 32 patients, for whom surgery was needed. Out of the 272 successfully treated patients, 8 developed cholangitis, 21 developed pancreatitis, and 10 patients had delayed bleeding, and no patient died. Among these 272 successful removal cases, successful bile duct stone removal was achieved after the first lithotripsy in 211 patients, whereas 61 patients underwent multiple sessions of lithotripsy. As for the 61 patients that underwent multiple sessions of mechanical lithotripsy, 6 (9.8%) had post-procedure cholangitis, 12 (19.6%) had pancreatitis, and 9 patients (14.7%) had delayed bleeding. Compared with the 211 patients undergoing a single session of mechanical lithotripsy, 3 (1.4%) had cholangitis, 1 (0.4%) had delayed bleeding, and 7 patients (3.3%) had pancreatitis. Statistical deviation was present in post-procedure cholangitis, delayed bleeding, and pancreatitis of both groups. CONCLUSION: Mechanical bile stone lithotripsy on difficult bile duct stones could produce around 90% successful rate. Moreover, complications are minimal. This finding further confirms the significance of mechanical lithotripsy in the treatment of patients with difficult bile duct stones.