THE CLINICAL INTRODUCTION OF A 3RD GENERATION LITHOTRIPTOR - MODULITHSL-20

The Modulith SL 20 was designed as a third generation lithotriptor wi th outstanding disintegrative efficacy in vitro, and equipped with a c ombined fluoroscopic and ultrasound localization system integrated in a multifunctional table. Its introduction to clinical extracorporeal s hock wave lithotripsy took place in 3 phases. In phase 1 (49 patients) only in line ultrasound localization was possible. The many caliceal stones were adequately disintegrated with restricted generator voltage . In phase 2 (81 patients) fluoroscopic localization with the virtual focus of an adapted x-ray C-arm unit enabled in situ lithotripsy of ur eteral stones in 33% of all patients. Phase 3 (549 patients) was chara cterized by additionally increasing the generator voltage to 20 kv. Th is development of the lithotriptor by improving the localization syste m and shock wave energy resulted in the possibility for successful dis integration of stones in the entire upper urinary tract (including the complete ureter), decreased treatment time (52 to 39 minutes) and an improved efficiency quotient (0.45 to 0.67). During phase 3 auxiliary measures were performed before lithotripsy in 24% of the cases. After 1.8% of the treatments minor or moderate perirenal fluid collection or bleeding was detected by routine followup sonography. A 91% stone-fre e rate was achieved with only 9.3% curative auxiliary measures after e xtracorporeal shock wave lithotripsy, including a 23% retreatment rate . Thus, the Modulith device had a high efficacy quotient compared with other lithotriptors.