Extracorporeal piezoelectric lithotripsy for retained bile duct stones.

Extracorporeal piezoelectric shock wave lithotripsy (EPL) was performed in 35 patients with endoscopically non-extractable stones. With this lithotripter, stones are visualized by ultrasound and shock waves are produced by a piezoelectric acoustic generator. The stones could be localized in 32 out of 35 patients. Fragmentation was achieved in 91.4% and complete stone removal in 77.1%. These results show that piezoelectric lithotripsy is also a useful method for the treatment of complicated bile duct stones, as already demonstrated for the electrohydraulically and electromagnetically generated shock waves systems. The piezoelectric system is especially useful in elderly and frail patients because no general anesthesia is needed and only 14% of cases require analgesia or sedation.