In vitro fragmentation of gallstones with lithotriptors for use in laparoscopic cholecystotomy.

In preliminary in vitro experiments, five different lithotriptors for use in laparoscopic cholecystotomy were tested to determine the fragmentation time and rate of a defined group of gallstones. The Alexandrit laser and the ultrasonic lithotriptor were too ineffective to warrant further investigation. In phantom tests with pig gallbladders, the pulsed dye laser and the electrohydraulic lithotriptor had a fragmentation rate of 100%, but the rate of clearing of the gallbladder was 0% as stone debris always remained in the gallbladder. The clearing rate of the RotoLith mechanical lithotriptor was 84.6%. The RotoLith lithotriptor was the most effective device because the stones were ground into such small particles that they could easily be rinsed out of the gallbladder. As the RotoLith procedure does not need to be monitored optically, the opening of the gallbladder need not exceed 3 mm compared to 10 mm for the other lithotriptors. This makes closure of the gallbladder safer and it would seem feasible to perform the procedure using the RothoLith lithotriptor under local anaesthesia.