Percutaneous extraction of renal and ureteral calculi: technical considerations.

Most renal calculi up to 12 mm in diameter and most upper-ureteral calculi can be removed intact percutaneously in one stage, using fluoroscopic rather than endoscopic control. By eliminating a second-stage fragmentation procedure (e.g., ultrasonic lithotripsy), hospital stays are shortened, costs are decreased, and morbidity is lessened. The techniques for percutaneous one-stage removal of upper urinary tract calculi are described.