Randomized study of intracorporeal laser lithotripsy versus extracorporeal shock-wave lithotripsy for difficult bile duct stones

Background: Endoscopic treatment modalities ape well established for the removal of bile duct stones. For the small percentage of stones that are difficult or impossible to extract by conventional means, more sophisticated endoscopic techniques or associated modalities such as intracorporeal laser lithotripsy (ILL) and extracorporeal shock wave lithotripsy (ESWL) have to be applied. Little is known, however, about the relative value of these different techniques. We therefore compared endoscopic ILL with ESWL in patients with difficult bile duct stones in a prospective randomized study. Methods: The study included 60 patients (35 women; mean age 70 +/- 15 years) with bile duct stones in whom standard extraction failed (n = 33) or in whom the papilla was not accessible, thus requiring percutaneous access (n = 27). They were randomized to receive ESWL under fluoroscopic targeting (maximum discharge number per session: 6000) or ILL using a pulsed dye laser with an automatic stone recognition system, which was mostly performed (28 of 30 cases) under cholangioscopic control. Endoscopic removal of fragments was attempted within the subsequent (ESWL) or the same (ILL) session. Failure was defined as failure to remove all ductal stones/fragments after a maximum of three lithotripsy sessions. Results: There were no statistical differences in background variables between the two groups. Bile duct clearance was achieved in 22 of 30 patients (73%) in the ESWL group and in 29 of 30 patients (97%) in the ILL group (p < 0.05). The number of treatment sessions (ESWL 3.0 +/- 1.3; ILL 1.2 +/- 0.4; p < 0.001) and the duration of treatment (ESWL 3.9 +/- 3.5 days; ILL 0.9 +/- 2.3 days; p < 0.001) were also significantly different in favor of ILL. Two minor complications occurred in each group; there was no 30-day mortality. Crossover therapy to ILL led to stone removal in seven of the eight cases in which ESWL failed, whereas ESWL fragmented the stone in the single patient in whom ILL failed. Conclusions: ILL is more effective in the treatment of difficult bile duct stones than ESWL in terms of stone clearance rate and treatment duration.