The efficiency of urolithiasis treatment with extracorporeal lithotripsy in relation to the shock waves frequency

To compare the results of two frequencies of shock waves (1 SW/1 sec. and 1 SW/2 sec.) in the treatment of urolithiasis using the shock wave lithotripsy.

SWL is the most frequent modality of the treatment of urolithiasis. The information on a better efficiency of applying shock waves of a lower frequency was proved both "in vitro" and "in vivo". After having corroborated the better efficiency of shock waves of lower frequency (1 SW per second) in extracorporeal lithotripsy, the authors compared it "in vitro" to still lower frequency (1 SW per 2 seconds). The still lower frequency did not result in any pronounced improvement of efficiency of extracorporeal lithotripsy. Now, the authors present the results of a study "in vivo".

The authors treated a set of 20 patients with urolithiasis of comparable size and location using the method of SWL and SW of identical intensity--20. The patients were divided into the two groups according to the frequency of the applied SW (A--1 SW/1 sec, B--1 SW/2 sec).

In the group A, fragmentation was observed in 100% after on average 3550 SW. In the group B, fragmentation was observed in 90% after on average 3100 SW, leaving of concrements was observed in 70% after on average 3465 SW.

The comparison of the results of two frequencies of shock waves (1 SW/1 sec and 1 SW/2 sec) in the treatment using SWL and the Piezolith 3000 device, did not prove any significant difference of effectiveness (Tab. 4, Ref. 16).