SWL for large urinary stones: Clinical insights into non-invasive treatment
Can large urinary stones be treated safely and effectively – without surgery or anaesthesia?
The clinical experience with over 2,000 Extracorporeal Shock Wave Lithotripsy (SWL) procedures shows that modern shock wave technology like the MODULITH® SLX-F2 »FD21« can reliably fragment even dense or unusually shaped stones measuring 1 cm or more – often in a single session. A structured protocol including preventive ureteral stenting demonstrates good clinical results without the need for invasive intervention.
In this expert article, Dr Nika Gagoshidze and Professor Guram Karazanashvili from the Karazanashvili Robotic Center in Tbilisi share their clinical insights and explain why SWL remains a reliable first-line therapy even for complex urinary stones.
Clinical results with SWL for large urinary stones
How effective is Extracorporeal Shock Wave Lithotripsy for treating urinary stones 1 cm and larger – and can it reliably reduce the need for repeat sessions? In our clinical practice, we aimed to answer this using a structured treatment protocol and modern SWL technology. Across 2,000 procedures, we found that even large, dense, or unusually shaped stones could be successfully treated in a single session – without the need for anaesthesia, and with minimal complications. Our data and clinical experience highlight SWL as a safe, non-invasive first-line option for managing complex urinary stones.
One session is often enough – regardless of stone size or density
We treated a broad range of stones using the MODULITH SLX-F2 »FD21« lithotripter, including:
- 780 kidney stones measuring 1–2 cm
- 326 kidney stones between 2–5 cm
- 10 kidney stones over 5 cm
- 135 ureteral stones measuring 1–2 cm
Notably, medical guidelines of the European Association of Urology recommend performing percutaneous nephrolithotomy (PNL) as first option and SWL as second option for stones between 2 and 5 cm in size. According to the standard, patients with stones between 2 and 5 cm were offered PNL as first option and SWL as second option. For stones larger than 5 cm surgical treatment was categorically offered to patients. We generally opted for SWL for patients with high risks of surgical complications or resistant infection.
From these cases, 1,238 stones had a density above 1,000 Hounsfield units yet fragmented efficiently. Overall, 76.2% of patients were stone-free at one month, with an additional 20.6% at three months, and 1.7% at six months. Only 84 patients (4.2%) required a repeat procedure. Patients were classified as stone-free when no residual calculi were identified on flat-panel X-ray images. Stone-free rates were assessed at one, two- and three-months following treatment.
Prioritising safety with preventive stenting
To reduce the risk of ureteral obstruction due to migrating fragments, ureteral stenting was performed in 1,366 cases prior to SWL. This approach proved both safe and effective. Notably, no patients experienced renal haematoma or sepsis, and only 17 cases required endoscopic follow-up for residual fragments in the ureter.
This data supports SWL not only as an efficient treatment, but also as a low-risk alternative to invasive procedures.
A patient-friendly option in stone management
Compared to surgical methods such as PNL or ureteroscopy (URS), SWL offers a clear advantage in terms of invasiveness, recovery and patient comfort. It avoids general anaesthesia, hospitalisation, and extended downtime.1
Advantages of our SWL protocol include:
- Non-invasive, outpatient treatment
- No general anaesthesia required
- Excellent outcomes in a single session
- Minimal post-treatment complications
- High acceptance among patients
Conclusion: a nuanced role for SWL in modern stone management
Our experience using the MODULITH SLX-F2 »FD21« shows that SWL – when applied with a structured protocol and appropriate patient selection – can achieve high success rates even for large and dense urinary stones. In our clinical setting, consistent outcomes were observed without general anaesthesia or invasive procedures, supported using preventive ureteral stenting.
It should be noted that short-term outcomes in randomised studies – including recent data comparing SWL and flexible Ureteroscopy (fURS) for 10–20 mm stones – often show higher stone-free rates for fURS in the early post-treatment period.1 However, long-term efficacy and safety profiles appear comparable, and SWL may offer advantages in terms of patient comfort, reduced pain, and specific quality-of-life parameters.
These findings underline the importance of individualised treatment decisions, considering both clinical context and broader evidence, and support the continued role of SWL as a valuable non-invasive option in stone management.
1 Erdoğan E, Kanberoğlu AF, Aşık A, Sarıca G, Sarica K. Outcomes of 10–20 mm Renal Stones: SWL vs. Flexible Ureteroscopy. Urologia Internationalis 2025 Mar 7: 1-7. DOI: 10.1159/000545108
