Stone-Free Rates: PCNL vs ICL (Intracorporeal Lithotripsy)
Direct Answer
PCNL achieves superior stone-free rates of 87-94% compared to intracorporeal lithotripsy techniques (ureteroscopy/RIRS) which achieve 81-90% for stones 10-20mm and approximately 75-81% for stones >20mm. 1, 2
Stone-Free Rates by Stone Size
Stones ≤10mm
- Ureteroscopy (URS) with intracorporeal lithotripsy: 90% stone-free rate 1, 2
- PCNL: Not typically first-line for this size range 1
- SWL achieves only 72% stone-free rate for comparison 2
Stones 10-20mm (Lower Pole)
- PCNL: 87% median stone-free rate 1, 2
- URS/RIRS with intracorporeal lithotripsy: 81% median stone-free rate 1, 2
- SWL drops to only 58% in this range 1
Stones >20mm
- PCNL: 87-94% stone-free rate 2, 3, 4
- RIRS with intracorporeal lithotripsy: 75-81% stone-free rate (single procedure) 2, 3
- Two-staged RIRS: Equivalent to PCNL stone-free rates, but only 26% require the second procedure 4
Network Meta-Analysis Findings
A comprehensive network meta-analysis of 35 studies directly comparing these modalities found: 5
- PCNL ranked #1 for stone-free rates across all stone sizes 5
- RIRS with intracorporeal lithotripsy had significantly lower stone-free rates than PCNL (OR 0.38; 95% CI 0.22-0.64) 5
- For stones ≥2cm specifically, PCNL was superior to RIRS (OR 4.68; 95% CI 2.87-8.11) 5
- For lower pole stones, PCNL was superior to RIRS (OR 1.98; 95% CI 1.04-2.85) 5
Cochrane Systematic Review Results
The most recent high-quality systematic review (2023) of 42 trials with 4571 participants found: 3
- PCNL improved stone-free rates by 13% compared to RIRS (RR 1.13,95% CI 1.08-1.18) 3
- This translates to 100 more stone-free patients per 1000 treated with PCNL versus RIRS 3
- PCNL reduced need for secondary interventions by 69% (RR 0.31,95% CI 0.17-0.55) 3
Trade-offs Between Modalities
PCNL Advantages
- Highest stone-free rates (87-94%) 2, 3, 5
- Fewer secondary interventions required (69% reduction vs RIRS) 3
- Shorter overall treatment period 6
PCNL Disadvantages
- 51% higher complication rate than RIRS (RR 1.51,95% CI 1.24-1.83) 4
- 82% higher Clavien-Dindo grade 2 complications (RR 1.82,95% CI 1.30-2.54) 4
- Hospital stay 1-2.6 days longer than RIRS 3, 4
- Higher blood transfusion rates 7
RIRS/Intracorporeal Lithotripsy Advantages
- Lower complication rates overall 4
- Shorter hospital stay (1-2.6 days less) 3, 4
- Can be repeated with minimal additional morbidity 4
Clinical Algorithm for Selection
For stones >20mm: PCNL is mandatory first-line therapy due to dramatically superior stone-free rates (87-94% vs 75-81%) 1, 2
For stones 10-20mm: PCNL achieves 87% vs 81% for RIRS—choose PCNL when single-procedure success is critical, or RIRS when patient factors favor lower morbidity 1, 2
For stones ≤10mm: RIRS with intracorporeal lithotripsy achieves 90% stone-free rate and is preferred over PCNL due to lower morbidity 1, 2
Critical Procedural Standards
- Flexible nephroscopy must be routine during PCNL to access fragments in areas inaccessible by rigid nephroscope, preventing residual stones 1, 2
- Normal saline irrigation is mandatory for both PCNL and intracorporeal lithotripsy procedures to prevent electrolyte abnormalities 1, 2
- Ho:YAG laser is the gold standard for intracorporeal lithotripsy during RIRS 2
Common Pitfalls
- Never offer SWL for stones >10mm as first-line therapy—stone-free rates drop to 58% for 10-20mm stones and only 10% for stones >20mm 1, 2
- Do not underestimate the impact of stone location—lower pole stones have significantly worse clearance with all modalities, but PCNL maintains superiority 5
- Avoid single-procedure RIRS for stones >20mm without counseling patients about the high likelihood (74%) of needing secondary interventions 3, 4