CU 60. In vitro comparison of two type of introcorporeal ultrasound lithotripsy device (CQS-01 and EMS-III/IV)

Objective: A new combination intracorporeal lithotripter (CQS-01) has been developed that incorporates the beneficial effects of pneumatic lithotripsy and ultrasound lithotripsy. An in vitro study was performed to assess the efficiency of stone fragmentation and clearance of this new intracorporeal ultrasound lithotripter compared with currently available ultrasound units (EMS-III/IV).

Methods: Twenty phantom stones made of dental gypsum were randomly divided into four groups, CQS-01 ultrasound lithotripter (70% power and 70% duty factor), EMS-III ultrasound lithotripter (70% power and 70% duty factor), EMS-IV ultrasound lithotripter (type A, 70% power and 70% duty factor) and EMS-IV ultrasound lithotripter (type B, 70% power and 100% duty factor) were used to fragment and remove phantom stones. The mean stone breakdown times and fragment removal times and stone fragment sizes for the standard ultrasound devices were compared to determine the completeness and efficiency of stone fragmentation and removal.

Results: The average time for stone breakdown was 7.4±1.7 s, 9.4±1.5 s, 82.2±12.6 s and 51.4±18.7 s, respectively, there was no significance between CQS-01 and EMS-III (P>0.05), but there was significance between CQS-01, EMS-III and EMS-IV (A and B); The average time for stone clearance using the ultrasound devices was 387.8±60.9 s, 411.6±51.5 s, 568±119.1 s and 383.6±75.6 s, respectively. The ultrasound units of CQS-I, EMSIII and EMS-IV(B) was efficient as same as (P>0.05), but there was significance between EMS-IV(A) and EMS-IV(B) (P<0.05). In addition, the average size of the largest fragments removed was the same (<3 mm).

Conclusions: The ultrasound capabilities in a newly developed lithotrite (CQS-01) exhibited the same ability to fragment and clear phantom stones compared with standard ultrasound devices alone. These preliminary studies suggest that this combination pneumatic/ultrasound lithotripter may be an ideal device for the expeditious removal of large-volume renal or bladder calculi. Additional studies are warranted to better assess the capabilities of this new device in treating humanstones of various compositions and its safety, as well as the optimal power and frequency settings.