Clinical experience with a new ultrasonic and LithoClast combination for percutaneous litholapaxy.

OBJECTIVE

To assess a new lithotripter for intracorporal lithotripsy, which combines the mechanically driven pneumatic LithoClast (Electro-Medical Systems, Nyon, Switzerland) and a new ultrasonic device (Electro-Medical Systems), for use in percutaneous nephrolitholapaxy (PNL).

PATIENTS AND METHODS

The new lithotripter consists of a LithoClast Master with 12 Hz repetition rate and a new ultrasonic device. The 1.0 mm LithoClast probe is advanced off-centre through the hollow 3.3 mm ultrasonic probe and protrudes about 1 mm. A new irrigation system with a pinch valve compressing the irrigation tube, a foot-switch for activating the ultrasound, the LithoClast and both together, and a stone bucket at the outlet tube are new features. Between February 1999 and August 2001, 68 patients were treated by PNL with the new device; 35 had complete and 33 had partial staghorn calculi. PNL was administered under fluoroscopic control and with the patient prone.

RESULTS

The mean (range) duration of surgery was 61 (42-119) min. The complete stone-free rate was 66% after the first PNL; of the 68 patients, 16 received a second PNL, giving a final stone-free rate of 76% and 80%. The stone was composed of calcium oxalate monohydrate (COM) in 13%, COM with uric acid in 35%, apatite in 20% and cystine in 11%. Clinically the new lithotripter was very effective, producing smaller stone particles and thus fewer residual stone fragments after PNL than with the LithoClast or ultrasonic fragmentation alone.

CONCLUSION

The new lithotripter provides easily managed and highly effective stone fragmentation of all stones, regardless of their composition.