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 pro-trudes 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) minutes. 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.

Source: BJU International (2002), 90, 16-19

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

Clinical efficacy of a combination pneumatic and ultrasonic lithotripter: The LithoClast® ultra.

Pietrow, Paul, Brian K. Auge, Pei Zhong, and Glenn M. Preminger
Duke University Medical Center, 1572D White Zone, DUMC 3167 Durham, NC, 27710, USA

Introduction

A new combination intracorporeal lithotriptor (LithoClast® Ultra, EMS, Nyon,
Switzerland) has been developed for percutaneous applications. It combines the stone clearing efficiency
of an ultrasonic device with the fragmentation strength of a pneumatic probe into a single handpiece.
Herein we present our initial clinical experience with this device in a prospective comparison between
the combination lithotrite and standard ultrasonic lithotripsy.

Methods

Twenty consecutive patients undergoing percutaneous nephrolithonomy (PNL) for
stone extraction were enrolled in the study. PNL was performed using a standard ultrasonic device
(Olympus, Melville, NY) in ten patients and the combination lithotrite was utilized in ten individuals.
Stone location and burden were assessed prior to the operative procedure. Stone clearance rates
(measured in mm2/minutes) were calculated for the two devices. Complications and stone-free rates
were compared between the two groups.

Results

Stone location and composition were similar in the two groups of patients. Average time
required for complete stone disintegration/extraction was considerably higher in the ultrasonic patients
43.7 minutes versus 21.1 minutes for those treated with the combination device, p = 0.036). The opposite
as true for the average rates of stone clearance (expressed in mm2/minutes), where the standard ultrasonic
device could clear 16.8 mm2/minutes versus 39.5 mm2/minutes for the combination lithotrite (p = 0.028).
Complications between the two groups were comparable.

Conclusion

Combination ultrasonic/pneumatic lithotripsy is capable of disintegrating and extracting
stone material at a more rapid rate than standard ultrasonic devices. Complication rates were
comparable between the two devices. Stone-free rates are slightly superior with the combination
lithotrite. This new device is efficacious and safe during the removal of large renal calculi.

Source: Oral presentation abstract at the World Congress of Urology in Genova (October 2002)