Improved results of extracorporeal shock wave lithotripsy with the Dornier MPL 9000 for single gallstones

Our aim was to compare the results of extracorporeal shock wave lithotripsy with the Dornier MPL 9000 for patients with single radiolucent gallstones less than or equal to 20-mm diameter using higher power (kV) and more shock waves during lithotripsy with our results during the Dornier National Biliary Lithotripsy Study using lower power and fewer shock waves. Nineteen patients were treated at higher power (mean +/- SE, 21.0 +/- 0.4 kV) vs 11 patients at lower power (18.8 +/- 0.5 kV). In the higher power group, the actuarial rate for complete clearance of gallstone fragments was 39 +/- 9%, 63 +/- 9% and 78 +/- 9% after 6 weeks, 3- and 6-months follow-up, respectively, versus only 19 +/- 12% after 6 months in the lower power group. We conclude that the use of higher power and more shock waves during extracorporeal shock wave lithotripsy with the MPL 9000 results in fragment clearance rates over 6 months for patients with single gallstones that are significantly higher than those previously achieved in the Dornier National Biliary Lithotripsy Study.