Comparative study of the efficacy of the electroimpulse and electrohydraulic lithotripters in vitro

Aim of the study was to compare the efficacy of the artificial stone désintégration between new nanosecond electroimpulse lithotripter (NSEIL) and standard electrohydraulic lithotripter (EGL). Two types of “stones” were used, which simulated hard and soft urinary stones and were made of dental ultrastrong gypsum BegoStone. EGL was performed using sounds of 3 diameters: 3.0 Fr, 4.5 Fr and 7.0 Fr; NSEIL - using sounds 2.7 Fr, 4.5 Fr and 6.0 Fr. Efficacy of the lithotripters was compared for wo comparable sounds with a one corresponding “stone” size. Afore mentioned “stones” were placed on the cage bottom made of stainless steel with a cell size of 2x2 mm, lying in the water with the home temperature. Experiment was considered to be finished, when at the surface of the cage there were no more visible “stone” fragments. The results obtained have showed, that desintegration of the artificial “stones” demanded substantially less energy and time in case of NSEIL. The part of the fully desintegrated “stones” with the use of NSEIL was 100%, taking in account that in 2 experiments EGL failed to fragmentize all the “stones”. Only in case of small energy impulses, small diameter of sounds and soft “stones” the similar results were obtained with regard to two investigated lithotripters. Otherwise electro-impulse lithotripsy demonstrated a significant advantage over the electrohydraulic lithotripsy. It was shown, that for NSEIL substantially lower summary values of energy are needed to desintegrate the “stone”.