The new generation Siemens Multiline lithotripter tube "M": early results in ureteral calculi

The Siemens electromagnetic Lithostar tube "C" and the new multiline tube "M" lithotripters were compared for the in situ treatment of ureteral calculi. A series of 248 patients with a calcium oxalate ureteral stone (proven by stone analysis) more than 4 mm in diameter were treated between December 1994 and September 1995 with the tube M Multiline lithotripter. The results were compared with those of 462 patients treated in prior years with tube C. High energy levels were obtained without sedation in 11% of patients with tube C and in 61% with tube M. The proportion of patients needing additional analgetics was 11% and 6%, respectively. The percentages of patients reporting no pain at all were 7 and 77. In proximal calculi, stone-free status was achieved in 63 of 79 patients (80%) with tube C and in 82 of 91 patients (90%) with tube M (p = 0.057). In distal calculi, stone-free status was achieved in 124 of 173 patients (72%) with tube C and in 134 of 157 patients (85%) with tube M (p = 0.0027). The evacuation rate for distal ureteral stones was significantly higher with tube M, which implies that the new shock head can enable the operator to apply higher energy without sedation because of the better tolerance.