Rassweiler J. et al., 2020: Extracorporeal shock-wave lithotripsy: is it still valid in the era of robotic endourology? Can it be more efficient?
Rassweiler J, Rieker P, Rassweiler-Seyfried MC.
Department of Urology, SLK Kliniken Heilbronn.
Department of Urology, Medical School Mannheim, University of Heidelberg, Heidelberg, Germany.
PURPOSE OF REVIEW: The aim of the article is to evaluate the actual role of extracorporeal shock-wave lithotripsy (ESWL) in the management of urolithiasis based on the new developments of flexible ureterorenoscopy (FURS) and percutaneous nephrolithotomy (PCNL).
RECENT FINDINGS: In Western Europe, there is a significant change of techniques used for treatment of renal stones with an increase of FURS and a decrease of ESWL. The reasons for this include the change of indications, technical improvement of the endourologic armamentarium, including robotic assistance. Mostly relevant is the introduction of digital reusable and single-use flexible ureterorenoscopes, whereas micro-PCNL has been abandoned. Some companies have stopped production of lithotripters and novel ideas to improve the efficacy of shock waves have not been implemented in the actual systems. Promising shock-wave technologies include the use of burst-shock-wave lithotripsy (SWL) or high-frequent ESWL. The main advantage would be the very fast pulverization of the stone as shown in in-vitro models.
SUMMARY: The role of ESWL in the management of urolithiasis is decreasing, whereas FURS is constantly progressing. Quality and safety of intracorporeal shock-wave lithotripsy using holmium:YAG-laser under endoscopic control clearly outweighs the advantages of noninvasive ESWL. To regain ground, new technologies like burst-SWL or high-frequent ESWL have to be implemented in new systems.
Curr Opin Urol. 2020 Mar;30(2):120-129. doi: 10.1097/MOU.0000000000000732.
The authors of this article pose the important and interesting question on the place of SWL (if any) in future urology. The relevance of this question is obvious when the recent literature I scrutinized. Reports from individual stone centres, systematic reviews and meta-analyses have presented unchallenged evidence that endoscopic methods (fURS, RIRS and PCNL) generally give better stone-free rates with a much lower need of repeated treatment sessions than is the case for SWL. These facts are thoroughly discussed in the article.
While we have witnessed amazing technical development of endoscopic methods, a similar development of SWL cannot be discerned. In some respects, it even can be concluded that SWL technology over time has moved in the opposite direction, at least when some modern devices are compared with the original Dornier HM3 equipment.
Before proceeding with this comment, it is important to make a distinction between SWL of stones in the kidney and stones in the ureter. With a relatively low need of repeated SWL sessions (mean 1.3) it was possible to achieve a stone-free rate around 97% (95.1 -97.8 %).
The percentage of patients requiring only ONE session are shown below .
It is my opinion, that for stones in the ureter the advantages of URS over SWL are exaggerated.
The situation is quite different for stones located in the kidney with a significantly lower stone-free rate. I agree that stone-free rates most certainly can be improved with modified methods for stone disintegration and thus maintain the non-invasive treatment approach.
As mentioned in this review article there are several interesting novel methods for stone disintegration:
Burst wave lithotripsy
Acoustic bubble coalescence
High frequency SWL
The effect of high frequency SWL cannot be found in the literature and I cannot comment on that, but the other techniques so far have been studied only experimentally. If any of these methods will be transferred to clinical applications seems highly reliant on urologists’ interest in such improvements. If urologists continue to be fully satisfied with what they can accomplish with endoscopic techniques, it might be wishful thinking that even significantly improved SWL will make this technique to a less boring method than what currently is the opinion among too many urologists.
It is important to repeat the advantages of non-invasive treatment. There is no need of general or regional anaesthesia and with adequate education of assisting nurses, there will be no need of an anaesthetist either. The procedures can be carried out without access to an operating theatre. In most patients, no special preparation is necessary and with rational organization, emergent treatment of ureteral stones is possible.
There are two factors that are essential for improved SWL technology:
Firstly, a company that is willing to transfer experimental techniques to clinically useful devices.
Secondly, a regained interest in SWL by urologists. This step will require urologists to return to the lithotripters to find out how SWL can be used and improved. Today, too many urologists have no or only very vague ideas of SWL.