Optimal Shock Wave Rate for Shock Wave Lithotripsy in Urolithiasis Treatment: A Prospective Randomized Study

Abstract

PurposeWe aimed to compare the effects of a fast shock wave rate (120 shocks per minute) and a slow shock wave rate (60 shocks per minute) on the shock wave lithotripsy (SWL) success rate, patient's pain tolerance, and complications.Materials and MethodsA total of 165 patients with radiopaque renal pelvis or upper ureter stones were included in the study. Patients were classified by use of a random numbers table. Group I (81 patients) received 60 shock waves per minute and group II (84 patients) received 120 shock waves per minute. For each session, the success rate, pain measurement, and complication rate were recorded.ResultsNo statistically significant differences were observed in the patients according to age, sex, body mass index, stone size, side, location, total energy level, or number of shocks. The success rate of the first session was greater in group I than in group II (p=0.002). The visual analogue pain scale was lower in group I than in group II (p=0.001). The total number of sessions to success and the complication rate were significantly lower in group I than in group II (p=0.001).ConclusionsThe success rate of SWL is dependent on the interval between the shock waves. If the time between the shock waves is short, the rate of lithotripsy success decreases, and the pain measurement score and complications increase. We conclude slow SWL is the optimal shock wave rate.

What are the Benefits and Harms of Ureteroscopy Compared with Shock-wave Lithotripsy in the Treatment of Upper Ureteral Stones? A Systematic Review

“…In all studies, SFRs were higher when shock waves were administered at a slower rate, reaching a statistically significant difference (p < 0.05) in one study [53]. One study showed that the mean number of SWL sessions required was reduced in patients undergoing fast SWL (p = 0.021) [51]. The other study showed that duration of procedure was significantly reduced in patients undergoing fast SWL compared to slow SWL (p < 0.001) [53].…”

“…In one study, there was no significant difference in the achieved SFR at 2 wk [50], whereas in the other study, these rates were improved by treating the patient prone rather than supine (90.6% vs 88.3%, p < 0.05) [49]. Three studies looked at whether the administered shock rate affected SFRs [51,53,56]. In all studies, SFRs were higher when shock waves were administered at a slower rate, reaching a statistically significant difference (p < 0.05) in one study [53].…”

Comparison of flexible ureteroscopy and percutaneous nephrolithotomy for the management of 10–20‐mm renal stones: A 5‐year retrospective study

“…When treating the stones located in the renal pelvis, SWL had a highest SFR (80–88 per cent), but the SFR decreased when treating upper pole stones (73 per cent), midpolar stones (69 per cent) and lower pole stones (63 per cent) . When treating multiple renal stones with SWL, SFR dropped to 50–55 per cent .…”

Comparison of treatment outcomes according to output voltage during shockwave lithotripsy for ureteral calculi: a prospective randomized multicenter study

“…Exclusion criteria included the following: (1) contraindications to SWL, (2) multiple UC, (3) febrile urinary tract infections, (4) a single kidney, (5) nonfunctioning kidney, (6) azotemia (creatinine > 1.8 mg/dl), (7) ureteral strictures, (8) severe hydronephrosis on imaging studies, (9) a past history of cystine stones, and (10) ureteral stent insertion before SWL due to colic.…”