Sihotang RC. et al., 2025: The comparison of totally ultrasound-guided versus fluoroscopy-guided shockwave lithotripsy in renal stone treatment: a systematic review and meta-analysis.

Retta Catherina Sihotang, Nur Rasyid, Ponco Birowo, Gerhard Reinaldi Situmorang, Widi Atmoko 
F1000Res. 2025 Jul 7;14:181. doi: 10.12688/f1000research.157981.2.  FREE FULL TEXT

Abstract

Extracorporeal shock wave lithotripsy (SWL) has been a well-known therapy since years ago, especially for renal stones less than 20 mm. This study compared the effectiveness of totally ultrasound-guided (US-guided) and fluoroscopy-guided (FS-guided) SWL in treating renal and ureteral stones. A protocol has been registered in PROSPERO databases for systematic reviews. A systematic literature search was conducted in five online databases (PubMed, ScienceDirect, EMBASE, ProQuest, and Scopus). We included all available articles that compared the effectiveness and safety of US-SWL to FS-SWL. A risk of bias assessment was done using Risk of Bias (Rob) Tools for randomized interventional studies and Risk of bias in non-randomized studies interventions (ROBINS-I) Tools for Non-randomized studies. The primary outcome was the stone-free rate, and the secondary outcome was the complication rate. Subgroup analyses were performed for adult and pediatric groups. A comprehensive literature search identified seven comparative articles that matched the criteria: two randomized trials and six retrospective cohort studies comprising 1,255 patients (609 using US-SWL). The results revealed a significant difference in overall stone-free rates between US-guided and FS-guided SWL RR 0.76(95% CI; 0.61-0.95, p=0.02) and in adults RR 0.76(95% CI; 0.60-0.96), but not children groups RR 0.68(95% CI; 0.24-1.88). US-SWL might be favourable due to the radiation-free procedure and real-time presentation. Complication rates were low, and no life-threatening complications were reported. In conclusion, US-guided SWL is more effective than FS-guided SWL for treating renal stones, with a low incidence of complications. Further randomized controlled trials with larger populations are needed to explore the comparison more accurately.

Comment Hans-Göran Tiselius

Successful SWL requires that the stone(s) are in precise focus and remain there during the procedure. To achieve that goal, it is necessary to use a well working imaging system. In that regard it was proven that fluoroscopic systems have had an advantage because they have been easy to learn and work with. The disadvantage is, however, that the technique results in a significant radiation load. This is generally problematic, but particularly so when children are treated. Successful SWL also might require repeated adjustments of the patient position to maintain the stone in focus and complete the treatment with a high hit rate.
During recent years ultrasound imaging systems have been improved and easier to use albeit a significant methodological education is necessary.
In the current article the authors have carried out a systematic review and meta-analysis of results obtained from a total of eight studies based on 1255 treated patients. It is of note that the stone-free rate with ultrasound was 52-93% and with fluoroscopy 40-90.5%. Like most other studies, the stone-free rates were lowest for stones in the lower calyces.
It is not mentioned how ultrasound was used in the treatment, but one advantage with this technique is that it can be used to continuously keep the stone in focus. If this can be arranged in a remote way it is certainly much easier to accomplish than to follow the stone at the treatment table. The latter approach can be an ergometric problem, but it is not mentioned how the ultrasound imaging was used, nor how the hit-rate was.
It is of note that the results indicate that the operators of both systems had a high level of expertise with both imaging systems.
The conclusion was that the treatment results with ultrasound-guided treatment was superior to that of fluoroscopic guided treatment. Calculations from Figure 4 showed ultrasound stone-free rates in children of 91% compared with 89% for fluoroscopy. The corresponding numbers for ultrasound and fluoroscopy were 76% and 79%, respectively.
It is of importance that modern education of SWL-operators should contain sufficient training in US-imaging. Moreover, it seems highly important to develop US-imaging systems that are sufficiently easy to work with.

Hans-Göran Tiselius