From the Guidelines
Extracorporeal shock wave lithotripsy (ESWL) can be a viable option for removing kidney stones, particularly for patients with small volume staghorn calculi and normal collecting-system anatomy, as an alternative to ureteral stenting.
Key Considerations
- The decision to use ESWL versus ureteral stenting depends on several factors, including stone size, location, composition, and patient health, as noted in the 2007 guideline for the management of ureteral calculi 1.
- ESWL is generally less invasive than stenting and does not require leaving a foreign body in place, making it an attractive option for patients who desire minimal anesthesia, as highlighted in the same guideline 1.
- However, ESWL may require multiple sessions for complete stone clearance, and patients might experience discomfort during fragment passage, as discussed in the context of managing ureteral calculi 1.
Stone Size and Location
- The effectiveness of ESWL is influenced by stone burden, with smaller stones (< 500 square millimeters) having significantly higher stone-free rates, as mentioned in the AUA guideline on management of staghorn calculi 2.
- The location of the stone within the ureter also affects the success rate of ESWL, with proximal ureteral stones having higher stone-free rates (82%) compared to mid (73%) and distal (74%) ureteral stones, according to the 2007 guideline 1.
Patient Health and Recovery
- Recovery from ESWL typically takes 1-2 days, and patients are recommended to take pain medication like acetaminophen or NSAIDs and increase fluid intake (2-3 liters daily) to help pass fragments and reduce discomfort.
- The choice between ESWL and ureteral stenting should be made on a case-by-case basis, considering the individual patient's health status, stone characteristics, and preferences, as implied by the guidelines 2, 1.
From the Research
Extracorporeal Shock Wave Lithotripsy (ESWL) as an Option for Kidney Stone Removal
- ESWL is considered a standard treatment for patients with upper-tract stones that are less than 10 mm in diameter 3
- For intermediate-sized upper-tract stones (100-300 mm2), ESWL can be a reasonably successful treatment alternative, especially for patients who are not fit for a general anesthetic or who prefer ESWL over competing treatments 3
- However, the success rate of ESWL is lower compared to percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS) for larger stones 3, 4
Comparison with Ureteral Stenting
- Ureteroscopy and laser stone fragmentation (URSL) has been shown to be a viable alternative to PCNL for large renal stones, with excellent outcomes and minimal morbidity 5
- Flexible ureterorenoscopy (RIRS) has been compared to ESWL for kidney stones ≤2 cm, with RIRS achieving better stone-free rates at 1 and 6 months, but not at 1 year 4
- ESWL remains a viable alternative, especially for 6-10-mm stones, providing comparable results to RIRS in the long term 4
Efficacy of ESWL
- ESWL has been shown to be effective for patients with stones smaller than 20 mm, with 65% of patients being stone-free after a minimum follow-up of 1 month 6
- Medical therapy following ESWL, such as nifedipine or tamsulosin, can facilitate ureteral stone expulsion and improve overall outcomes 7
- However, patients with larger stones (20 mm or larger) may require multiple treatment sessions and have less favorable results 6