Never	<25%	>25%, <50%	Approx. 50%	>50%, <75%	>75%	Always
Ultrasound
Pneumatic
Laser
Electro-hydraulic
Combined ultrasound/pneumatic
No lithotripsy

PCNL – percutaneous nephrolithotomy; CIRF – clinically insignificant residual fragment; KUB – kidneys ureters and bladder; CT – computed tomography