Comparison of Efficacy of German and Chinese Electromagnetic Shock Wave Lithotripters: Dornier Compact S vs Huikang MZ-SWL-V

Abstract

To compare the treatment efficacy of Dornier Compact S and a Chinese electromagnetic shock wave lithotripter (Huikang MZ-SWL-V) in a large series. We retrospectively reviewed the outcome of shock wave lithotripsy (SWL) in 13,954 consecutive patients with upper urinary tract stones from December 1996 to December 2008 with Dornier Compact S (9124 cases) and Huikang MZ-SWL-V (4830 cases). An intramuscular injection of 50 mg pethidine was given to the patients with Dornier Compact S but not to those with Huikang MZ-SWL-V. Treatment outcomes were assessed by the stone-free rate at three months, the retreatment rate, the auxiliary procedure rate, and the effectiveness quotient. The pain scores were evaluated by visual analog scales, where 0 = pain and 10 = unbearable pain. The overall stone-free rate at 3 months, retreatment rate, and ancillary procedure rate for Dornier Compact S were 95.9%, 13.4%, and 2.2%, respectively, and they were 85%, 29.6%, and 10.2%, respectively, for Huikang MZ-SWL-V. The overall efficiency quotients of Dornier Compact S and Huikang MZ-SWL-V were 83% and 60.8%, respectively. However, the pain scores in the Dornier group (6-10) were higher than those in the Huikang group (1-5). Three clinically significant subcapsular hematomas were detected in the Dornier group but there were none in the Huikang group. Dornier Compact S is more effective than Huikang MZ-SWL-V, but SWL with Huikang machine could be performed with milder pain and without analgesia, and a lower significant hematoma rate was observed in Huikang group.