Abstract

Abstract

PURPOSE: We compared the clinical outcomes of patients with ureteral or renal stones treated with ureteroscopy, shock wave lithotripsy using HM3 (Dornier®) and nonHM3 lithotripters, and percutaneous nephrolithotomy.

MATERIALS AND METHODS: A systematic literature search identified 6, 4 and 3 randomized, controlled trials of treatment of distal and proximal ureteral stones, and renal stones, respectively, published between 1995 and 2010. Overall stone-free, re-treatment and complication rates were calculated by meta-analytical techniques.

RESULTS: Based on the randomized, controlled trials evaluated the treatment of distal ureteral stones with semirigid ureteroscopy showed a 55% greater probability (pooled RR 1.55, 95% CI 1.13-2.56) of stone-free status at the initial assessment than treatment with shock wave lithotripsy. Patients treated with semirigid ureteroscopy were also less likely to require re-treatment than those treated with shock wave lithotripsy (nonHM3) (RR 0.14, 95% CI 0.08-0.23). The risk of complications was no different between the 2 modalities. Only 2 of the 4 randomized, controlled trials identified for proximal ureteral stones evaluated flexible ureteroscopy and each focused specifically on the treatment of stones 1.5 cm or greater, limiting their clinical relevance. The degree of heterogeneity among the studies evaluating renal stones was so great that it precluded any meaningful comparison.

CONCLUSIONS: Semirigid ureteroscopy is more efficacious than shock wave lithotripsy for distal ureteral stones. To our knowledge there are no relevant randomized, controlled trials of flexible ureteroscopy treatment of proximal ureteral calculi of a size commonly noted in the clinical setting. Collectively the comparative effectiveness of ureteroscopy and shock wave lithotripsy for proximal ureteral and renal calculi is poorly characterized with no meaningful published studies.

Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

J Urol. 2012 Jul;188(1):130-7. doi: 10.1016/j.juro.2012.02.2569. Epub  2012 May 15

PMID: 22591962 [PubMed - in process]

Comment

Comment

The aim of this study was to compare ESWL and URS in their capacity to disintegrate distal and proximal ureteral stones based on RCTs found in the literature. Only few RCTs were identified and conclusions were possible to draw only for distal ureteral stones. It thereby was concluded, that semirigid URS was more efficacious than ESWL, with a 55% greater probability of being successful. No meaningful conclusions were possible for proximal ureteral or renal stones.

Although RCT studies are considered to give definite information on the results that should be expected with different forms of active stone removal, it is important, to be aware of the various factors that influence the outcome. Different lithotripters, different techniques applied and different experience by the operators play an important role. It is often very difficult to fully elucidate this complex situation. In my own series of distal ureteral stones consecutively and consistently treated with the Storz Modulith SLX lithotripters the stone-free after one session was 83.2% and the mean number of sessions required to achieve a stone-free ureter in 98% of the patients was 1.22. That outcome is obviously better than the results obtained in the RCTs referred to. Although a faster stone-free rate in expert hands certainly can be achieved with URS for distal ureteral stones, the non-invasive approach can give fully acceptable results.

Hans-Göran Tiselius