ESWL - Shockwave Lithotripsy for Kidney Stones

ESWL is most effective for kidney stones up to 10mm in diameter. International guidelines (EAU) recommend ESWL as an appropriate first-line option for renal stones up to 20mm in select locations (non-lower pole), but success rates decline significantly above 15mm. For lower pole stones, stone-free rates with ESWL are lower (around 55–60% for 10–15mm stones) compared to RIRS. For stones smaller than 4–5mm, natural passage may be awaited with medical expulsive therapy before considering ESWL. Dr. Nitin will review your CT scan and advise whether ESWL is the right treatment for your specific stone.

ESWL is performed as an outpatient procedure. Discomfort ranges from minimal to moderate depending on stone depth and shockwave energy used. Modern lithotripters deliver waves at lower energy with better targeting, reducing pain. Intravenous sedation and analgesia are given to ensure comfort during the 30–45 minute session. Most patients describe feeling a tapping or pressure sensation. Post-procedure, you may experience dull flank ache and discomfort as stone fragments pass - typically managed with oral analgesics (ibuprofen or paracetamol) for 2–5 days.

A single session is planned initially, with success assessed by KUB X-ray or ultrasound at 4–6 weeks. If significant stone burden remains, a repeat session may be offered. Up to 3 sessions may be needed for larger or harder stones (calcium oxalate monohydrate stones are particularly resistant to shockwaves). If two sessions have not cleared the stone adequately, alternative treatment (RIRS or PCNL) should be considered rather than continuing with multiple ESWL sessions.

ESWL is contraindicated in: pregnancy (shockwaves are harmful to the foetus); uncorrected bleeding disorders or active anticoagulation; active urinary tract infection (treat infection first); anatomical obstruction below the stone (fragments cannot pass); very obese patients (stone cannot be adequately targeted); patients with cardiac pacemakers in certain positions. Relative contraindications: lower pole stones >10mm (lower stone-free rates - RIRS preferred), very hard stones (Hounsfield units >1000 on CT - ESWL unlikely to work), and ureteric stones (RIRS is superior for mid and lower ureter).

After ESWL, stone fragments typically pass in the urine over 4–6 weeks. You may notice gravel or grit in the urine. Occasionally, a "steinstrasse" (street of stones) can form - a column of fragments obstructing the ureter. This may cause ureteric colic (loin-to-groin pain) and requires intervention if it does not resolve. Fragments that remain at 6 weeks need reassessment - further ESWL, RIRS ureteroscopy, or in rare cases PCNL depending on size and location. Dr. Nitin reviews all post-ESWL results and plans next steps accordingly.

ESWL (shockwave lithotripsy) uses external focused sound waves - no incision, no anaesthesia, outpatient. Treats small to medium stones that can be precisely targeted. RIRS (retrograde intrarenal surgery / laser ureteroscopy) uses a flexible camera passed through the natural urinary tract - day case surgery, no incision, excellent stone-free rates for stones up to 2cm. PCNL (percutaneous nephrolithotomy) uses a small track through the back directly into the kidney - best for large or staghorn stones. ESWL is the most non-invasive; RIRS gives better stone-free rates with comparable recovery; PCNL is reserved for the largest stones. Dr. Nitin chooses based on stone size, location, density, and patient factors.