Extracorporeal shockwave lithotripsy (ESWL)

Mechanism and typical setting

Acoustic energy is coupled into the flank over the stone with image guidance. The session is usually performed on a lithotripter table, often under sedation or light general anaesthesia, and commonly lasts about 30 to 45 minutes, as described on the Urology NSW kidney stone page.

Where ESWL fits best

• Stones under approximately 1 cm in the kidney, particularly in the renal pelvis or upper and middle calyces, and selected ureteric stones, remain common ESWL indications in contemporary practice.
• For stones smaller than about 1 cm, flexible ureteroscopy and ESWL can perform similarly in stone-free terms in many analyses, while ESWL offers shorter procedure time and avoids an anaesthetic-related hospital stay in suitable patients.

Limitations and guideline positioning

Stone-free rates vary with stone size and density. Meta-analyses have reported higher stone-free rates with flexible ureteroscopy than with ESWL for stones in the 1 to 2 cm range; for smaller stones the gap narrows. Very hard stones on CT (high Hounsfield units), obesity, and unfavourable anatomy reduce ESWL success.

The American Urological Association (AUA) kidney stone guideline statements (2026) include expert opinion advising against ESWL as first-line for lower-pole kidney stones larger than 1 cm, or non-lower-pole kidney stones larger than 2 cm. For lower-pole stones larger than 1 cm, the AUA states that percutaneous nephrolithotomy (PCNL) is associated with a higher stone-free rate than either ESWL or ureteroscopy (strong recommendation, Grade A). European Association of Urology (EAU) urolithiasis guidance (2025) is used alongside the same imaging and patient factors in Australian practice.

Anticoagulation and bleeding risk

ESWL is generally not recommended while a patient is on anticoagulant or antiplatelet therapy, because of bleeding risk around the kidney. If stone treatment cannot wait and blood thinners cannot be paused, endoscopic laser lithotripsy is often discussed because it avoids shockwave tissue effects.

Recovery and follow-up

• ESWL is usually a day procedure.
• Passage of small fragments over days to weeks can cause intermittent loin discomfort.
• Bruising over the flank and blood in the urine are common in the first 24 to 48 hours.

Sometimes more than one ESWL session is needed, and a small proportion of stones are refractory to shockwaves. Ureteroscopy with holmium laser lithotripsy is the usual next step when ESWL does not clear the stone.

Patient leaflet

The BAUS patient leaflet ESWL for kidney and ureteric stones is available on this site as a PDF download.

Compare with holmium laser URS